This section is from the book "Manual Of Useful Information", by J. C Thomas. Also available from Amazon: Manual of useful Information.
Intrumental, conducive, assistant, helping, ministerial. Insufficiency, inadequacy, incompetency, incapability, deficiency, lack. Insult, affront,outrage, indignity, blasphemy. (Honor.) Insulting, insolent, rude, saucy, impertinent, impudent, abusive. Integrity, uprightness, honesty, probity, entirety, entireness, completeness, rectitude, purity. (Dishonesty.) Intellect, understanding, sense, brains, mind, intelligence, ability, talent, genius. (Body.) Intellectual, mental, ideal, metaphysical. (Brutal.) Intelligible, clear, obvious, plain, distinct. (Abstruse.) Intemperate, immoderate, excessive, drunken, nimious, inordinate. (Temperate.) Intense, ardent, earnest, glowing, fervid, burning, vehement. Intent, design, purpose, intention, drift, view, aim, purport, meaning. Intercourse, commerce, connection, intimacy, acquaintance. Interdict, forbid, prohibit, inhibit, proscribe, debar, restrain from. (Allow.) Interfere, meddle, intermeddle, interpose. Interminable, endless, interminate, infinite, unlimited, illimitable, boundless, limitless. (Brief, concise.) Interpose, intercede, arbitrate, meditate, interfere, meddle. Interpret, explain, expound, elucidate, unfold, decipher. Intimate, hint, suggest, insinuate, express, signify, impart, tell.
Intimidate, dishearten, alarm, frighten, scare, appal, daunt, cow, browbeat. (Encourage.) Intolerable, insufferable, unbearable, insupportable, unendurable. Intrepid, bold, brave, daring, fearless, dauntless, undaunted, courageous, valorous, valiant, heroic, gallant, chivalrous, doughty. (Cowardly, faint-hearted.) Intrigue, plot, cabal, conspiracy, combination, artifice, ruse, amour. Intrinsic, real, true, genuine, sterling, native, natural. (Extrinsic.) Invalidate, quash, cancel, overthrow, vacate, nulify, annul. Invasion, incursion, irruption, inroad, aggression, raid, fray. Invective, abuse, reproach, railing, censure, sarcasm, satire.. Invent, devise, contrive, frame, find out, discover, design. Investigation, examination, search, inquiry, research, scrutiny. Inveterate, confirmed, chronic, malignant. (Inchoate.) Invidious, envious, hateful, odious, malignant. Invigorate, brace, harden, nerve, strengthen, fortify. (Enervate). Invincible, unconquerable, impregnable, insurmountable. Invisible, unseen, imperceptible, impalpable, unperceivable. Invite, ask, call, bid, request, allure, attract, solicit. Invoke, invocate, call upon, appeal, refer, implore, beseech. Involve, implicate, entangle, compromise, envelope.
Irksome, wearisome, tiresome, tedious, annoying. (Pleasant.) Irony, sarcasm, satire, ridicule, raillery. Irrational, foolish, silly, imbecile, brutish, absurd, ridiculous. (Rational.) Irregular, eccentric, anomalous, inordinate, intemperate. (Regular.) Irreligious, profane, godless, impious, sacrilegious, desecrating. Irreproachable, blameless, spotless, irreprov-able. Irresistible, resistless, irrepressible. Irresolute, wavering, undetermined, undecided, vacillating. (Determined.) Irritable, excitable, irascible, susceptible, sensitive. (Calm.) Irritate, aggravate, worry, embitter, madden, exasperate. Issue, v., emerge, rise, proceed, flow, spring, emanate. Issue, n., end, upshot, effect, result, offspring, progeny.
Jade, harass, weary, tire, worry. Jangle, wrangle, conflict, disagree. Jarring, conflicting, discordant, inconsonant, inconsistent. Jaunt, ramble, excursion, trip. Jealousy, suspicion, envy. Jeopard, hazard, peril, endanger. Jest, joke, sport, divert, make game of. Journey, travel, tour, passage. Joy, gladness, mirth, delight. (Grief.) Judge, justice, referee, arbitrator. Joyful, glad, rejoicing, exultant. (Mournful.) Judgment, discernment, discrimination, understanding. Justice, equity, right. Justice is right as established by law; equity according to the circumstances of each particular case. (Injustice.) Justness, accuracy, correctness, precision.
Keep, preserve, save. (Abandon.) Kill, assassinate, murder, slay. Kindred, affinity, consanguinity, relationship. Knowledge, erudition, learning, science. (Ignorance.)
Labor, toil, work, effort, drudgery. (Idleness.) Lack, need, deficiency, scarcity, insufficiency. (Plenty.) Lament, mourn, grieve, weep. (Rejoice.) Language, dialect, idiom, speech, tongue. Lascivious, loose, unchaste, lustful, lewd, lecherous. (Chaste.) Last, final, latest, ultimate. (First.) Laudable, commendable, praiseworthy. (Blamable.) Laughable, comical, droll, ludicrous. (Serious.) Lawful, legal, legitimate, licit. (Illegal.) Lead, conduct, guide. (Follow.)
Lean, meager. (Fat.) Learned, erudite, scholarly. (Ignorant.) Leave, v., quit, relinquish. Leave, n., liberty, permission, license. (Prohibition.) Life, existence, animation, spirit, vivacity. (Death.) Lifeless, dead, inanimate. Lift, erect, elevate, exalt, raise. (Lower.) Light, clear, bright. (Dark.) Lightness, flightiness, giddiness, levity, volatility. (Seriousness.) Likeness, resemblance, similarity. (Unlikeness.) Linger, lag, loiter, tarry, saunter. (Hasten.) Little, diminutive, small. (Great.) Livelihood, living, maintenance, subsistence, support. Lively, jocund, merry, sportive, sprightly, vivacious. (Slow, languid, sluggish.) Long, extended, extensive. (Short.) Look, appear, seem. Lose, miss, forfeit. (Gain ) Loss, detriment, damage, deprivation. (Gain.) Loud, clamorous, high-sounding, noisy. (Low, quiet.) Love, affection. (Hatred.) Low, abject, mean. (Noble.) Lunacy, derangement, insanity, mania, madness. (Sanity.) Luster, brightness, brilliancy, splendor. Luxuriant, exuberant. (Sparse.)
Machination, plot, intrigue, cabal, conspiracy. (Artlessness.) Mad, crazy, delirious, insane, rabid, violent, frantic. (Sane, rational, quiet.) Madness, insanity, fury, rage, frenzy. Magisterial, august, dignified, majestic, pompous, stately. Make, form, create, produce. (Destroy.) Malediction, anathema, curse, imprecation, execration. Malevolent, malicious, virulent, malignant. (Benevolent.) Malice, spite, rancor, ill-feeling, grudge, animosity, ill-will. (Benignity.) Malicious, see malevolent. Manacle, v., shackle, fetter, chain. (Free.) Manage, contrive, concert, direct. Management, direction, superintendence, care, economy. Mangle, tear, lacerate, mutilate, cripple, maim. Mania, madness, insanity, lunacy. Manifest, v., reveal, prove, evince, exhibit, display, show. Manifest, a., clear, plain, evident, open, apparent, visible. (Hidden, occult.) Manifold, several, sundry, various, divers, numerous. Manly, masculine, vigorous, courageous, brave, heroic. (Effeminate.) Manner, habit, custom, way, air, look, appearance. Manners, morals, habits, behavior, carriage. Mar, spoil, ruin, disfigure. (Improve.) March, tramp, tread, walk, step, space. Margin, edge, rim, border, brink, verge. Mark, n., sign, note, symptom, token, indication, trace, vestige, track, badge, brand.
 
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