inhibit, inhibited, inhibiting, inhibits.transitive verbs
to hold back; restrain; curb; to prohibit; forbid
inhibition.noun
the act of inhibiting or the state of being inhibited; something that restrains, blocks, or suppresses; conscious or unconscious restraint of a behavioral process, a desire, or an impulse
inhibitable, inhibitive.or.inhibitory.adjectives

intelligence.noun
the ability to understand  from observation, experience and attention, by using comparisons and selecting  those things which are deemed valuable enough to retain for effectively solving problems, directing conduct, responding to new experiences, etc.; also the ability to recognize those things appealing to the intellect, including purposeful design, etc. (a rabbit would not recognize the intelligence in a book pre schoolers would)
intelligent.adjective
having or using intelligence

intention.noun
determination to do a specific thing (I intend to go downtown)
intend, intended, intending, intends.verbs
transitive use-to have in mind; plan (we intend to go, they intend going, you intended that she go); to design for a specific purpose; to have in mind for a particular use; to signify or mean
intransitive use-to have a design or purpose in mind

intent.noun
something that is intended; an aim or a purpose; intention; meaning
intent.adjective
firmly fixed; concentrated (an intent gaze); aving the attention applied; engrossed (the students, intent upon their books, did not hear me enter the room); having the mind and will focused on a specific purpose (was intent on leaving within the hour; are intent upon being recognized)
Law.–.the state of one's mind at the time one carries out an action
idiom-for all intents and purposes or to all intents and purposes; in every practical sense; practically (to all intents and purposes the case is closed; to direct attention
intently.adverb
intentness.noun

intensity.noun
very strong (as intense light is hard on the eyes)
intense, intenser, intensest.adjectives
possessing or displaying a distinctive feature to an extreme degree (the intense sun of the tropics); extreme in degree, strength, or size (intense heat); involving or showing strain or extreme effort (intense concentration); deeply felt; profound (intense emotion); tending to feel deeply (an intense writer)
intensely.adverb
intensness.noun
see 'intend'

interconversion, interconvertibility.nouns
mutual conversion (interconversion of chemical compounds) 
interconvert.transitive verb 
interconvertible.adjective

interrogate.transitive verb
to formally ask questions of; examine by questioning 
synonym-ask

interrogatory.adjective
formal question or set of questions

inverse.adjective
reversal; inverted; directly opposite

ipso facto.adverb
by the fact or act itself; by that very fact

intron.noun
a segment of a gene situated between axons that does not function in coding for protein-synthesis; (from, 'intragenic', meaning, occurring within a gene)

idiot.noun
a foolish or stupid person; the term belongs to a classification system no longer in use and is now considered offensive

idiotic.adjective
very foolish or stupid; characteristic of an idiot
idiocy.noun
the state of being an idiot

immutable.adjective
never changing or varying 
immutability.noun
immutably.adverb
in an immutable manner

in vitro.adverb-or.adjective
outside the living body and in an artificial environment

in vivo.adverb.or.adjective
in the living body of a plant or animal

indoctrinate.transitive verb 
inflected form(s)-indoctrinated; indoctrinating
to imbue with a usually partisan or sectarian opinion, point of view, or principle; brainwash
indoctrination, indoctrinator.nouns

inevitable.adjective
that cannot be avoided or evaded; certainly

isolate, isolated, isolating.transitive verbs
to put out in the Sun for drying, bleaching, etc. 
isolate as an.adjective-separated and alone; to set apart from others; 
isolation.noun
the action of isolating; the condition of being isolated 
synonym-solitude

immense.transitive verb
limitless; infinite; very large; vast; huge; enormous
immensely.adverb
immenseness.noun

induce, induced, inducing, induces.transitive verbs
to lead on to some action; persuade; to bring about; cause

intersperse, interspersed, interspersing.transitive verbs
to scatter among other things; put here and there; to decorate and diversify with things scattered here and there 
interspersion.noun