Advanced Vocabulary Starting with "I"

237 entries

• iatrogenic Caused by medical treatment or a healthcare professional. It describes illnes...
• iconic Widely recognised and well-established as a representative symbol of somethin...
• iconoclast A person who challenges or attacks widely accepted beliefs, institutions, or ...
• iconoclastic Challenging or attacking cherished beliefs, institutions, or established valu...
• idealism In philosophy, the view that reality is fundamentally mental or spiritual rat...
• idealist A person who is guided by high principles and a vision of how things ought to...
• idempotent Describing an operation or function that produces the same result when applie...
• ideology A system of ideas and ideals forming the basis of a political, economic, or s...
• idiopathic Describing a disease or condition that arises spontaneously or from an unknow...
• idiosyncratic Peculiar or individual to a specific person; distinctive and unconventional i...
• idyllic Extremely happy, peaceful, or picturesque, often in a way that seems too perf...
• ignominy Public shame, disgrace, or dishonour, especially as a consequence of humiliat...
• illicit Forbidden by law, rules, or social convention; illegal or not permitted. Ofte...
• illuminate To light up a place or object, or figuratively to clarify or shed light on a ...
• illustrious Well known and admired for outstanding achievements or qualities; famous and ...
• imbue To pervade or inspire with a particular quality, feeling, or idea; to fill or...
• immaculate Perfectly clean, tidy, or neat; free from any flaw or error.
• immanence The quality of being inherent or existing within something; in theology, the ...
• immersion Deep involvement or engagement in an activity or environment; in language edu...
• imminent About to happen very soon, typically used for events that are expected within...
• immunisation The process of making a person or animal immune to an infectious disease, typ...
• immunity Protection against or exemption from something, especially a disease or legal...
• immunology The branch of medicine and biology that studies the immune system, including ...
• immutable Unchanging over time; unable to be altered or changed.
• impair To weaken or damage something, especially a faculty or function, so that it n...
• impartial Treating all sides or parties equally, without favouritism or prejudice, espe...
• impartiality The quality of treating all parties, sides, or viewpoints equally and fairly,...
• impasse A situation in which no progress is possible, especially because of disagreem...
• impassive Showing no feeling or emotion; not affected by or responsive to something tha...
• impeccable Faultless and beyond criticism; conforming to the highest standards.
• impedance The total opposition that a circuit presents to alternating current, combinin...
• impede To obstruct or slow the progress of something, creating barriers that make it...
• impediment A hindrance or obstruction in doing something; a defect in speech such as a l...
• impenetrable Impossible to pass through, enter, or understand. Describing something so den...
• imperative A verb mood used to give commands, instructions, or requests, typically using...
• imperceptible So slight, gradual, or subtle as to be impossible or almost impossible to per...
• imperial Relating to an empire or its ruler; commanding and magnificent in scale or ma...
• imperialism A policy of extending a country's power and influence through colonisation, m...
• imperious Domineering and overbearing; assuming authority in an arrogant or high-handed...
• impervious Not allowing passage through; unable to be affected or influenced by somethin...
• impetuous Acting quickly and without careful thought or consideration; driven by sudden...
• impetus The force or energy with which something moves; a driving force or stimulus b...
• implacable Impossible to appease, pacify, or satisfy; relentless and unyielding in hosti...
• implant A medical device or piece of tissue that is placed inside the body through su...
• implausible Not seeming reasonable or probable; difficult to believe.
• implicit Implied or suggested without being directly or openly stated, requiring the l...
• implore To beg someone earnestly and desperately to do something; to plead with great...
• impound To seize and take legal custody of property, especially a vehicle, either as ...
• impoverish To make poor or reduce to poverty; to diminish the quality, richness, or stre...
• impoverished Made poor; reduced to a state of poverty. Also used figuratively to describe ...
• impregnable Unable to be captured, entered, or breached by attack; strong enough to resis...
• impressionism A 19th-century art movement originating in France, characterised by the use o...
• impromptu Done or made without preparation or advance planning; created on the spur of ...
• impudent Showing a bold lack of respect; shamelessly cheeky or insolent, especially to...
• impulsive Acting or done without forethought, driven by a sudden urge rather than delib...
• impunity Exemption from punishment or from the unpleasant consequences of an action; f...
• inadvertent Not resulting from or achieved through deliberate planning; unintentional, ac...
• inadvertently Without intention or by accident; as a result of inattention rather than deli...
• inane Silly, senseless, or lacking any significance; extremely foolish or pointless.
• inaugurate To begin or introduce something new, especially a system, policy, or period; ...
• incandescent Emitting light as a result of being heated to a high temperature; figurativel...
• incarcerate To imprison or confine someone; to keep a person locked up, especially as a p...
• incarnation A person or thing regarded as embodying a quality or idea in physical form; a...
• incendiary Designed to cause fires; figuratively, tending to inflame passions, provoke c...
• incessant Continuing without pause or interruption; unceasing and relentless.
• incessantly Without interruption or pause; continuing constantly in a way that is often p...
• incidence The rate at which new cases of a disease or condition occur in a population o...
• incipient Beginning to happen or develop; in an initial or early stage.
• incision A clean, deliberate cut made into the body with a sharp instrument, typically...
• incisive Showing clear, sharp thinking and an ability to identify the most important a...
• incite To encourage or stir up violent, unlawful, or undesirable behaviour in others...
• inclement Unpleasantly cold, wet, or stormy; used almost exclusively to describe harsh ...
• inclination A tendency or preference towards a particular course of action, belief, or wa...
• inclusion The practice or policy of ensuring that all people, regardless of their backg...
• inclusive Ensuring that all people, regardless of background, ability, or identity, are...
• incoherent Lacking logical connection or clarity, making it difficult to understand; use...
• incomprehensible Impossible to understand or make sense of; not able to be grasped by the mind.
• inconceivable Not capable of being imagined or believed; beyond what the mind can conceive ...
• incongruity The state of being incongruous; a lack of harmony or compatibility between th...
• incongruous Not in harmony or keeping with the surroundings, context, or expectations; st...
• inconsistency The quality of not being consistent; a contradiction or lack of agreement bet...
• inconspicuous Not clearly visible or attracting attention; not conspicuous.
• incontrovertible Not able to be denied or disputed; unquestionable and beyond doubt.
• incorrigible Beyond correction or reform; stubbornly resistant to change, especially in ba...
• incredulous Feeling or showing an inability or unwillingness to believe something; expres...
• increment A regular, usually small increase in quantity, value, or degree; in employmen...
• incremental Relating to or denoting an increase or addition, especially one of a series o...
• incrementally In a series of small, gradual steps or additions rather than all at once; by ...
• incubation The process of keeping eggs warm so that they will hatch; the period between ...
• incubator An enclosed apparatus providing controlled conditions of temperature and humi...
• inculcate To instil a belief, attitude, or habit in someone by persistent instruction o...
• incumbent The current holder of an official position, or (as adjective) necessary as a ...
• indefensible Not justifiable by argument; too bad or wrong to be defended or excused. Also...
• indelible Making marks that cannot be removed or erased; not able to be forgotten or wa...
• indemnification Compensation or reimbursement for loss, damage, or liability incurred; the co...
• indemnify To compensate someone for harm, loss, or damage, or to secure them against fu...
• indemnity Protection or security against financial loss or legal liability; also, a sum...
• indeterminate Not precisely fixed, known, or established; vague, uncertain, or impossible t...
• indicative The most common verb mood, used to state facts, ask questions, and describe r...
• indictment A formal charge or accusation of a serious crime; figuratively, something tha...
• indifferent Having no particular interest or sympathy; unconcerned. Also: of mediocre qua...
• indigenous Originating or occurring naturally in a particular place; used especially of ...
• indiscriminately Without careful distinction or selection; applied or carried out without rega...
• indispensable Absolutely necessary and impossible to do without; essential to the functioni...
• individualist A person who advocates or practises independence and self-reliance; relating ...
• indolent Wanting to avoid activity or exertion; habitually lazy and disinclined to wor...
• indomitable Impossible to subdue or defeat; having an unconquerable spirit or determination.
• inductance The property of an electrical conductor or circuit that opposes changes in cu...
• induction The process of reasoning from specific observations to a general conclusion; ...
• indulgent Allowing oneself or another to have excessive pleasures; overly tolerant or l...
• industrialisation The large-scale development of industry in a country or region, typically inv...
• industrialise To develop industries on a wide scale in a country or region, transforming an...
• industrious Diligent and hardworking; consistently and energetically productive.
• ineffable Too great, extreme, or profound to be expressed or described in words; beyond...
• inept Lacking skill or ability; clumsy, incompetent, or awkward in performance. Can...
• inequality The state of being unequal, especially in terms of status, rights, opportunit...
• inert Lacking the ability or will to move or act; in chemistry, not reacting with o...
• inertia The tendency of an object to resist changes in its state of motion; figurativ...
• inevitably As is certain to happen; unavoidably, in a way that cannot be prevented regar...
• inexorable Impossible to stop or prevent; continuing relentlessly and unavoidably. Also,...
• inexorably In a way that is impossible to stop or prevent; relentlessly and without yiel...
• inexplicable Unable to be explained or accounted for; baffling and mysterious.
• inextricable Impossible to disentangle, separate, or escape from; so closely linked that t...
• infamous Well known for some bad quality, deed, or reputation; famous for negative rea...
• infantry Soldiers who fight on foot, typically forming the largest component of an arm...
• infer To deduce or conclude something from evidence and reasoning rather than from ...
• inference A conclusion reached on the basis of evidence and reasoning, rather than from...
• infiltrate To enter or gain access to an organisation or place secretly and gradually, e...
• infinitesimal Extremely small; too small to be measured or to have any significant effect. ...
• infinitive The base form of a verb, typically preceded by 'to' in English (e.g., 'to run...
• inflammation A localised physical condition in which part of the body becomes reddened, sw...
• inflammatory Intended to arouse angry or violent feelings. In medicine, relating to or cau...
• inflection A change in the form of a word, typically by adding a suffix or modifying the...
• influencer A person with the ability to influence the purchasing decisions or opinions o...
• infographic A visual representation of information, data, or knowledge designed to presen...
• infrared Electromagnetic radiation with wavelengths longer than visible red light but ...
• infrasound Sound waves with a frequency below the lower limit of human hearing (typicall...
• infrastructure The basic physical and organisational structures needed for the operation of ...
• infusion The slow introduction of a substance, especially a liquid drug or nutrient, i...
• ingenuity The quality of being clever, original, and inventive; the ability to devise c...
• ingratiate To deliberately gain favour with someone through flattery or obsequious behav...
• inherent Existing as a natural, permanent, or essential quality or characteristic of s...
• inherently As a permanent, essential, or characteristic feature; by nature, in a way tha...
• inheritance Property, money, or a title received from someone who has died; the reception...
• inhibition A feeling that prevents one from acting naturally or expressing oneself freel...
• initiate To cause a process or action to begin; to introduce someone to a new activity...
• injective Describing a function in which every element of the codomain is mapped to by ...
• injunction A court order requiring a person or organisation to do or refrain from doing ...
• innate Inborn; existing from birth rather than acquired through experience or learni...
• innocuous Not harmful or offensive; unlikely to provoke any reaction.
• innovative Introducing or featuring new ideas or methods; advanced and original.
• inoculation The introduction of a pathogen or antigen into a living organism to stimulate...
• inordinately To an unusually or disproportionately large degree; beyond what is considered...
• inpatient A patient who is formally admitted to a hospital and occupies a bed for at le...
• insatiable Impossible to satisfy; always wanting more and never feeling that one has eno...
• inscription Words or symbols carved, engraved, or written on a surface such as stone, met...
• inscrutable Impossible to understand or interpret; giving no indication of what one is th...
• insidious Proceeding in a gradual, subtle way but with harmful effects; treacherous and...
• insipid Lacking flavour, interest, or vigour; dull and uninspiring.
• insolvency The state of being unable to pay debts when they fall due; the condition of h...
• instantiation A concrete example or single occurrence of something abstract; in computing, ...
• instigate To bring about or initiate an action or event, especially one that involves c...
• instigator A person who initiates or brings about an action or event, typically one invo...
• instinctive Arising from natural impulse or tendency rather than from deliberate thought ...
• institutionalise To establish something as a standard practice within an organisation or socie...
• instrumental Serving as a crucial means of achieving or accomplishing something; having a ...
• insular Ignorant of or uninterested in cultures, ideas, or peoples outside one's own ...
• insulation Material used to prevent the passage of heat, sound, or electricity. Also, th...
• insulator A material or device that resists the flow of electric current, heat, or soun...
• insurable Eligible or suitable for insurance coverage; meeting the criteria that allow ...
• insurgent A person who rises in active revolt against an established authority or gover...
• insurrection A violent uprising against an established authority or government; an organis...
• intangible Unable to be touched or grasped physically; difficult to define, measure, or ...
• integrable Capable of being integrated, particularly in the mathematical sense of having...
• integral In mathematics, the result of integration: a function whose derivative is a g...
• integration The process of combining or incorporating different elements into a unified w...
• intensify To become or make stronger, more extreme, or more concentrated in degree or f...
• intentional Done on purpose; carried out by design rather than by accident or coincidence.
• intercede To intervene on behalf of someone else, typically to resolve a dispute, preve...
• interface A point of interaction between two systems, devices, or subjects; in computin...
• interim Provisional or temporary; relating to the intervening period of time before s...
• interject To insert a remark or comment abruptly into a conversation or discussion, oft...
• interjection A word or phrase that expresses a sudden emotion or reaction, typically stand...
• interlocutor A person who takes part in a dialogue or conversation, particularly someone w...
• interminable Seemingly endless and tediously long, used to describe experiences, processes...
• intermittent Occurring at irregular intervals; not continuous or steady, stopping and star...
• intermittently At irregular intervals; stopping and starting repeatedly rather than continui...
• interoperability The ability of different systems, devices, or organisations to work together ...
• interpolate To insert something between existing elements; in mathematics, to estimate a ...
• intersectionality The interconnected nature of social categorisations such as race, class, gend...
• intonation The rise and fall of the voice in speech, particularly the pattern of pitch c...
• intractable Extremely difficult to manage, resolve, or deal with. In computing, describes...
• intransigent Unwilling or refusing to change one's views or to agree about something; unco...
• intransitive Describing a verb that does not take a direct object, expressing an action or...
• intravenous Administered directly into a vein, typically via a needle or cannula. Commonl...
• intrepid Fearless and adventurous, especially in the face of danger or difficulty. Use...
• intricacy The quality of being intricate; complex details or elaborate inner workings.
• intricate Having many complex, interrelated parts or details that require careful atten...
• intrinsic Belonging to the essential nature of a thing; existing within and not depende...
• intrinsically In a way that belongs to the essential nature of something; by its very natur...
• introspective Inclined to examine one's own thoughts, feelings, and motivations; given to s...
• introvert A person whose personality is characterised by a preference for quiet, minima...
• intubation The insertion of a tube into the body, most commonly into the trachea (windpi...
• intuitive Based on or proceeding from instinctive feeling rather than conscious reasoni...
• inundate To overwhelm with a great quantity of something, or literally to flood an are...
• invalidate To render something no longer valid, legally binding, or logically sound; to ...
• invariably In every case or on every occasion; always, without exception or variation.
• invective Insulting, abusive, or highly critical language directed at a person or group...
• inverse Opposite or reversed in position, direction, order, or effect. As a noun, the...
• invertible Capable of being reversed or inverted. In mathematics, describes a function o...
• investigative Relating to or involving systematic inquiry, research, or examination, especi...
• inveterate Having a particular habit, belief, or activity that is long-established and u...
• invigilator A person who supervises students during an examination to ensure that rules a...
• invigorate To give strength, vitality, or fresh energy to something or someone, making t...
• invincible Too powerful to be defeated or overcome; unconquerable.
• inviolable That which must not be transgressed, infringed, or dishonoured. Describes rig...
• invoke To cite or appeal to a law, principle, authority, or precedent as justificati...
• ionic Relating to or involving ions — atoms or molecules that carry an electrical c...
• irascible Having or showing a tendency to be easily angered; hot-tempered by nature rat...
• iridescent Showing luminous colours that seem to shift and change when viewed from diffe...
• irony The expression of meaning through language that normally signifies the opposi...
• irreconcilable Impossible to bring into harmony or agreement; so fundamentally opposed that ...
• irrefutable Impossible to deny, disprove, or refute; absolutely certain and beyond challe...
• irremediable Impossible to cure, correct, or put right; beyond remedy.
• irreparable Not able to be repaired, rectified, or made good; resulting in damage or harm...
• irreversible Not able to be undone, reversed, or restored to a former condition; permanent.
• irrevocable Not able to be changed, reversed, or recovered; final and unalterable.
• irrevocably In a way that cannot be changed, reversed, or recovered; permanently and beyo...
• ischaemia An inadequate blood supply to a part of the body, caused by narrowing or bloc...
• isometric Having equal measurements or dimensions. In exercise science, it describes mu...
• isomorphic Having the same form or structure, or in mathematics, describing a one-to-one...
• isotope One of two or more forms of the same chemical element that have equal numbers...
• isotopic Relating to or involving isotopes — atoms of the same chemical element that h...
• isthmus A narrow strip of land connecting two larger landmasses, with water on either...
• iterate To repeat a process or procedure, typically refining the result with each cyc...
• iteration The repetition of a process or procedure, especially in order to achieve a de...
• iterative Involving repetition of a process or procedure, with each cycle building on t...