15-Letter Words Starting With I

Complete list of 15-letter words that start with the letter I. Perfect for Scrabble, Wordle, and word game strategies. Found 546 words.

This page lists all 15-letter words that begin with the letter I. Learning these common words will help you excel at word games like Scrabble, Words with Friends, and Wordle.

546 words found

15-letter words 546

ichthyosauridae noun

later ichthyosaurs of the Jurassic and Cretaceous

ideographically adverb

in an idiographic manner

ignominiousness noun

unworthiness meriting public disgrace and dishonor

illustriousness noun

the property possessed by something or someone of outstanding importan…

imaginativeness noun

the formation of a mental image of something that is not perceived as …

immunochemistry noun

the field of chemistry concerned with chemical processes in immunology…

immunologically adverb

from the point of view of immunology

immunopathology noun

the branch of immunology that deals with pathologies of the immune sys…

impecuniousness noun

a state of lacking money

impenetrability noun

the quality of being impenetrable (by people or light or missiles etc.)

imperishability noun

the property of being resistant to decay

impermeableness noun

the property of something that cannot be pervaded by a liquid

implausibleness noun

the quality of provoking disbelief

impressionistic adjective

of or relating to or based on an impression rather than on facts or re…

inaccessibility noun

the quality of not being available when needed

inadmissibility noun

unacceptability as a consequence of not being admissible

inapplicability noun

irrelevance by virtue of being inapplicable to the matter at hand

inappropriately adverb

in an inappropriate manner

inattentiveness noun

a lack of attentiveness (as to children or helpless people)

incommensurable adjective

impossible to measure or compare in value or size or excellence

incommunicative adjective

not inclined to talk or give information or express opinions

incommutability noun

the quality of being not interchangeable

incompatibility noun

the relation between propositions that cannot both be true at the same…

incomprehension noun

an inability to understand

incomprehensive adjective

not comprehensive

incongruousness noun

the quality of disagreeing

inconsequential adjective

lacking worth or importance

inconsiderately adverb

without consideration

inconsideration noun

the quality of failing to be considerate of others

inconspicuously adverb

in a manner intended to avoid attracting attention

indemnification noun

a sum of money paid in compensation for loss or injury

indetermination noun

the quality of being vague and poorly defined

indigestibility noun

the property of being difficult to digest

indisputability noun

the quality of being beyond question or dispute or doubt

individualistic adjective

marked by or expressing individuality

industriousness noun

persevering determination to perform a task

ineffectiveness noun

lacking the power to be effective

ineffectualness noun

lacking the power to be effective

inefficaciously adverb

in an ineffective manner

inexpensiveness noun

the quality of being affordable

injudiciousness noun

lacking good judgment

innumerableness noun

a number beyond counting

inopportuneness noun

the quality of occurring at an inconvenient time

inquisitiveness noun

a state of active curiosity

insensitiveness noun

the inability to respond to affective changes in your interpersonal en…

insignificantly adverb

in an insignificant manner

inspirationally adverb

with inspiration

instantaneously adverb

without any delay

institutionally adverb

by an institution

instrumentalism noun

a system of pragmatic philosophy that considers idea to be instruments…

instrumentalist noun

someone who plays a musical instrument (as a profession)

instrumentality noun

a subsidiary organ of government created for a special purpose

instrumentation noun

an artifact (or system of artifacts) that is instrumental in accomplis…

insubordination noun

defiance of authority

insubstantially adverb

not substantially

insurrectionary adjective

of or relating to or given to insurrection

insurrectionism noun

the principle of revolt against constituted authority

insurrectionist noun

a person who takes part in an armed rebellion against the constituted …

intelligibility noun

the quality of language that is comprehensible

intemperateness noun

consumption of alcoholic drinks

intensification noun

action that makes something stronger or more extreme

interchangeable adjective

(mathematics, logic) such that the arguments or roles can be interchan…

interchangeably adverb

in an interchangeable manner

intercollegiate adjective

used of competition between colleges or universities

interconnection noun

a state of being connected reciprocally

interdependence noun

a reciprocal relation between interdependent entities (objects or indi…

interdependency noun

a reciprocal relation between interdependent entities (objects or indi…

interestingness noun

the power of attracting or holding one's attention (because it is unus…

internalization noun

learning (of values or attitudes etc.) that is incorporated within you…

internationally adverb

throughout the world

interreflection noun

reciprocal reflection between two reflecting surfaces

interrogatively adverb

in a questioning format

interscholastic adjective

used of competition or cooperation between secondary schools

intractableness noun

the trait of being hard to influence or control

intramuscularly adverb

in an intramuscular way

intussusception noun

the folding in of an outer layer so as to form a pocket in the surface

involuntariness noun

the trait of being unwilling

invulnerability noun

having the strength to withstand attack

irreligiousness noun

the quality of not being devout

irresistibility noun

the quality of being overpowering and impossible to resist

irreversibility noun

the quality of being irreversible (once done it cannot be changed)

isoagglutinogen noun

an antigen capable of causing the production of (or reacting with) an …