What is the Latin word for uselessly?

The usual Latin words for “uselessly” are inūtilis, frūstrā, nēquīquam; also in cassum. The right choice depends on the sense; see the distinctions below.

English → Latin

“uselessly” in Latin

inūtilisuseless, unserviceable, unprofitable; hurtful, injurious; void, null, invalid, without any legal use frūstrāin deception, in error; without effect, to no purpose, without cause, uselessly, in vain, for nothing nēquīquamIn vain, vainly, needlessly, uselessly, fruitlessly, pointlessly; to no purpose or effect, without ground or reason in cassumin vain

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

uselessly

inutiliter.

In vain, frustra: nequidquam: incassum (Sall., Liv.) [SYN. in VAINLY]. Not uselessly, non ex vano (not non temere, which is “not readily,” “not easily”).

Quick answer

What is the Latin word for uselessly?: The usual Latin words for “uselessly” are inūtilis, frūstrā, nēquīquam; also in cassum. 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.