What is the Latin word for useless?

The usual Latin words for “useless” are inūtilis, cāsus, inānis; also vānus, irritus, labor. The right choice depends on the sense; see the distinctions below.

English → Latin

“useless” in Latin

inūtilisuseless, unserviceable, unprofitable; hurtful, injurious; void, null, invalid, without any legal use cāsusa fall, downwards movement; accident, chance; an event, happening, occurrence inānisempty, void, hollow; vain; purposeless, meaningless, worthless, useless, fruitless, empty, idle vānusvain, empty, vacant, void; unsubstantial; groundless, baseless, meaningless, pointless, worthless, ineffectual, mindless irritusinvalid, void, null and void; ineffective, useless, irrelevant laborwork; labor, toil, exertion; hardship, trouble, fatigue, suffering, drudgery, distress vōtumpromise, dedication, vow, solemn pledge; determination, will, desire; prayer, devotion formīdōto dread or fear; to be afraid of or for cōgitātiōthinking, meditation, reflection; thought; reasoning contentiōstretching, tension; competition, rivalry; struggle, effort

Riddle & Arnold A Copious and Critical English–Latin Lexicon, 1864

useless

inutilis (not useful): cassus (empty, hollow; then profitless, causeless; e.g., labores, vota, formido): inanis (empty, without substance; hence unreal, profitless; e.g., cogitatio: contentiones): vanus (empty, without any useful result; e.g., ictus, inceptum): irritus (done in vain; e.g., inceptum, preces, labor). (The words are found in this connection and order.) vanus et irritus: irritus et vanus. Useless talk [Vid: FRIVOLOUS]. Useless things, inutilia: cassa, inania, etc.: nugae (trifles). To take useless trouble, operam perdere; operam frustra insumere, consumere, conterere; frustra laborem suscipere: to be just taking so much useless trouble, oleum et operam perdere (Cic., proverbially): saxum sarrire (Proverbially, to hoe a rock, Martialis): imbrem in cribrum ingerere (to catch the rain in a sieve, proverbially, Plaut., Pseud., 1, 1, 100): laterem lavare (to wash a tile, proverbially, Ter., Phorm., 1, 4, 9). Useless for anything, inutilis alicui rei or ad aliquid: useless to anybody, inutilis ad alicujus usum: a totally useless person, homo ad nullam rem or ad nullam partem utilis: to be useless, inutilem esse; nulli usui esse.

Quick answer

What is the Latin word for useless?: The usual Latin words for “useless” are inūtilis, cāsus, inānis; also vānus, irritus, labor. The right choice depends on the sense; see the distinctions below.

Entry from J. E. Riddle & T. K. Arnold, A Copious and Critical English–Latin Lexicon (rev. C. Anthon, New York: Harper, 1864), digitised by Fergus J. P. Walsh, CC BY-SA 4.0; Latin markup adapted by latindictionary.co.