1902, from French, literally "free verse," lines of varying length.

I remarked some years ago, in speaking of vers libre, that 'no vers is libre for the man who wants to do a good job.' The term, which fifty years ago had an exact meaning in relation to the French alexandrine, now means too much to mean anything at all. [T.S. Eliot, introduction to "Selected Poems of Ezra Pound," 1928]

"the order being changed," c. 1600, Latin, from vice, ablative of vicis "a change, alternation, alternate order" (from PIE root *weik- (2) "to bend, to wind") + versa, feminine ablative singular of versus, past participle of vertere "to turn, turn about" (from PIE root *wer- (2) "to turn, bend"). "The phrase has the complete force of a proposition, being as much as to say that upon a transposition of antecedents the consequents are also transposed" [Century Dictionary].

"an occasional pastime, an activity other than that for which one is well-known, or at which one excells," 1963, from French, literally "Ingres' violin," from the story that the great painter preferred to play his violin (badly) for visitors instead of showing them his pictures.

Une légende, assez suspecte, prétend que le peintre Ingres état plus fier de son jeu sur le violon, jeu qui était fort ordinaire, que de sa peinture, qui l'avait rendu illustre. [Larousse du XXe Siecle, 1931]