impediment.noun
something that impedes; a hindrance or an obstruction; obstacle; an organic defect preventing clear articulation.(a speech impediment)
Law.-.something that obstructs the making of a legal contract; to impede
impedimental.or.impedimentary.adjective

impede, impeded, impeding, impedes.transitive verbs
delay; hinder; retard or obstruct the progress of; hamper; impede suggests a slowing up of movement or progress by interfering with normal action (tight belts impede the normal circulation of blood)
impeder.noun

intervene, intervened, intervening, intervenes.intransitive verbs
to come, appear, or lie between two things (you can't see the lake from there because the house intervenes); to come or occur between two periods or points of time (a year intervened between the two dynasties); to occur as an extraneous or unplanned circumstance (he would have his degree by now if his laziness hadn't intervened); to come in or between so as to hinder or alter an action (intervened to prevent a fight); to interfere, usually through force or threat of force, in the affairs of another nation
intervenor or intervener, intervention.nouns
interventional.adjective

infidelity.noun, plural.infidelities
unfaithfulness to a sexual partner, especially a partner one has committed to; an act of sexual unfaithfulness; lack of fidelity or loyalty (infidelity to the family tradition, infidelity to the principles of the revolution); lack of religious belief

instil also instill, instilled, instilling, instils also instills
to introduce by gradual, persistent efforts; implant ("morality . . . may be instilled into their minds" ...Thomas Jefferson); to pour in (medicine, for example) drop by drop
instillation, instiller, instillment.nouns

incense, incensed, incensing, incenses.transitive verbs
to cause to be extremely angry; infuriate
incense.noun
an aromatic substance, such as wood or a gum, that is burned to produce a pleasant odor; the smoke or odor produced by the burning of such a substance
incense (2nd meaning), incensed, incensing, incenses.transitive verbs
to perfume with incense; to burn incense to, as a ritual offering

infuriate, infuriated, infuriating, infuriates.transitive verbs
to make furious; enrage
infuriate.adjective
infuriatingly.adverb
infuriation.noun

indispensable.adjective
not to be dispensed with; essential; obligatory; unavoidable (the routine but indispensable ceremonies of state)
indispensable.noun
one that is indispensable
indispensability or indispensableness.noun
indispensably.adverb

incontrovertible.adjective
impossible to dispute; unquestionable
incontrovertibility or incontrovertibleness.noun
incontrovertibly.adverb

interact, interacted, interacting, interacts.intransitive verbs
to act on each other

interaction.noun
the act or process of interacting; the state of undergoing interaction
Physics.-.any of four fundamental ways in which elementary particles and bodies can influence each other, classified as strong, weak, electromagnetic, and gravitational

immoderate.adjective
exceeding normal or appropriate bounds; extreme (immoderate eating); excessive
immoderately.adverb
immoderateness.or.immoderation.noun

inexhaustible.adjective
that cannot be entirely consumed or used up (an inexhaustible supply); never wearying; tireless (an inexhaustible campaigner) inexhaustibility.or.inexhaustibleness.noun
inexhaustibly.adverb

insensitive.adjective
not sensitive; numb; lacking in sensitivity to the feelings or circumstances of others; unfeeling; lacking in responsiveness (insensitive to the needs of customers)
insensitively.adverb
insensitivity.or.insensitiveness.noun

include, included, including, includes.transitive verbs
to take in as a part, an element, or a member (thanked the host for including us)
includable.or.includible.adjective

involve, involved, involving, involves.transitive verbs
to contain as a part; include.(was told that the job would involve travel); to engage as a participant
involvement, involver.nouns

instance.noun
an example that is cited to prove or invalidate a contention or illustrate a point; example; an occurrence.(in all such instances, let conscience be your guide)
instance, instanced, instancing, instances.transitive verbs
to offer as an example; cite; to demonstrate or show by an example; exemplify
for instance.idiom
as an example; for example

intransigent.adjective
refusing to moderate a position, especially an extreme position; uncompromising
intransigence, intransigent.nouns
intransigently.adverb

indebted.adjective
morally, socially, or legally obligated to another; beholden

indebtedness.noun
the state of being indebted; something owed to another

interpersonal.adjective
relating to, occurring among, or involving several people
interpersonally.adverb

immerse, immersed, immersing, immerses.transitive verbs
to cover completely in a liquid; submerge; to engage wholly or deeply; absorb (scholars who immerse themselves in their subjects)

indelicate.adjective
offensive to established standards of propriety; improper; marked by a lack of good taste; coarse; lacking in consideration for the feelings of others; tactless
indelicately.adverb
indelicateness.noun

indelicacy.noun, plural.indelicacies
the quality or condition of being indelicate; something indelicate

inconceivable.adjective
impossible to comprehend or grasp fully; so unlikely or surprising as to have been thought impossible; unbelievable (an inconceivable victory against all odds)
inconceivability.or.inconceivableness.noun
inconceivably.adverb

Indic.also called Sanskritic.adjective
of or relating to India or its peoples or cultures