Imperious - commanding, domineering, haughty, imperative, proud, lordly, overbearing, tyrannical.

Impertinent - rude, quarrelsome, intrusive, insolent, meddling, irrelevant, troublesome.

Impetuous - hasty, rough, vehement, violent, forcible, boisterous.

Implicate - involve, embarrass, entangle.

Implore - beg, beseech, ask, entreat, supplicate, solicit, request.

Imply - mean, signify, denote, infer, involve.

Importance - weight, moment, signification, consequence.

Imposture - deceit, cheat, fraud, deception, imposition, counterfeit, artifice.

Imprecation - execration, curse, malediction, anathema.

Improve - cultivate, correct, reform, rectify, amend, advance.

Impudent - insolent, bold, rude, saucy, impertinent, uncouth, immodest, shameless.

Impute - charge, ascribe, attribute.

Inability - disability, weakness, impotence.

Inactive - sluggish, lazy, idle, slothful, inert, drowsy.

Inadequate - insufficient, incompetent, unable, incapable.

Inattentive - negligent, heedless, careless, inadvertent, thoughtless, dilatory, remiss.

Incessantly - constantly, continually, unremitingly, unceasingly.

Incident - contingency, circumstance, event.

Incite - provoke, excite, stimulate, arouse, encourage, animate, aggravate.

Include - contain, enclose, comprise, embrace, comprehend.

Incommode - molest, disturb, inconvenience, trouble, annoy.

Incompetent - inapt, insufficient, incapaole, inadequate, unsuitable.

Inconsistent - incongruous, contrary, ridiculous, absurd.

Inconstant - unstable, uncertain, fickle, variable, changeable, versatile.

Indecent - unbecoming, impudent, immodest, indelicate.

Indicate - show, mark, point out, reveal.

Indifferent - passive, neutral, regardless, unconcerned, impartial.

Indigence - poverty, need, want, penury.

Indigenous - native.

Indignation - temper, anger, displeasure, contempt, resentment, wrath.

Indiscretion - imprudence, folly, injudiciousness.

Indispensable - important, necessary, essential.

Indisputable - undeniable, indubitable, unquestionable, incontrovertible, conclusive, settled.

Indistinct - confused, ambiguous, doubtful, dark.

Induce - persuade, lead, influence, urge, instigate, actuate.

Industrious - diligent, persevering, laborious, assiduous, active.

Inevitable - unavoidable, certain.

Inexorable - immovable, relentless, unyielding, implacable.

Inexpedient - unsuitable, unfit, inconvenient.

Infect - taint, corrupt, defile, contaminate, pollute. Inference - deduction, conclusion.

Inferior - less, lower, secondary, subservient, subordinate.

Infested - disturbed, troubled, annoyed, plagued.

Infinite - boundless, unbounded, illimitable, unlimited, immense, eternal.

Infirm - weak, sickly, decrepit, feeble, debilitated, imbecile.

Influence - authority, power, persuasion, credit, favor, sway.

Information - notice, counsel, intelligence, advice, instruction.

Ingenious - inventive, talented, skillful.

Ingenuity - capacity, invention, genius, skill, talent.

Inhabit - dwell, occupy, reside, stay, abide, sojourn.

Inherent - innate, inborn, inbred.

Inhuman - cruel, savage, barbarous, brutal.

Iniquitous - unjust, evil, wicked, nefarious.

Injunction - order, mandate, precept, command.

Injure - harm, hurt, impair, damage, deteriorate.

Innate - natural, inherent, inbred, inborn.

Innocent - pure, blameless, guiltless, faultless, inoffensive, harmless, spotless.

Inordinate - immoderate, intemperate, irregular, excessive.

Inquisitive - curious, inquiring, anxious, prying.

Insanity - derangement, madness, craziness, lunacy, mania.

Insensibility - dullness, apathy, indifference, stupidity, torpor, imperceptibility.

Insidious - deceitful, sly, crafty, cunning, subtle treacherous.

Insignificant - worthless, meaningless, inconsiderable, trivial, unimportant.

Insinuate - hint, suggest, intimate.

Insolent - insulting, abusive, rude, haughty, saucy, offensive, impertinent.

Inspire - animate, invigorate, enliven, cheer, exhilarate, suggest.

Instigate - tempt, incite, urge, encourage, impel, move, stimulate.

Instill - infuse, implant, sow.

Instruction - education, precept, teaching, suggestion, counsel, advice.

Insufficient - inadequate, incapable, incompetent, unfit, unable, unsuitable.

Insult - abuse, affront, outrage, contempt, insolence, indignity.

Integrity - purity, probity, truthfulness, uprightness, honesty.

Intellect - understanding, genius, ability, capacity, talent.

Intelligence - intimation, understanding, information, notice, knowledge, intellect.

Intemperate - excessive, immoderate, inordinate.

Intend - purpose, mean, design.

Intercede - mediate, interpose, interfere.

Interline - insert, alter, correct, add.

Intermission - cessation, stop, rest, vacation, interruption.

Intermit - abate, suspend, subside, forbear.

Interpose - mediate, interfere, intermeddle.

Interpret - explain, demonstrate, elucidate, expound, decipher.

Interrogate - examine, question, inquire.

Interval - space, interstice, time.

Intervening - coming between, interposing, intermediate.

Intimidate - frighten, alarm, daunt, scare.

Intoxication - infatuation, inebriety, drunkenness.

Intractable - perverse, obstinate, stubborn, ungovernable, uncontrollable, unmanageable.

Intrepid - fearless, undaunted, bold, daring, valiant, courageous, brave.

Intrinsic - real, true, inherent, inward, essential, genuine.

Introductory - preliminary, previous, prefatory.

Intrude - invade, infringe, encroach, obtrude, entrench. Intrust - confide, commit.

Invade - enter, attack, intrude, encroach, infringe. Invalid - weak, sick, infirm, null, feeble, void.