potissimus
From LSJ
Σκηνὴ πᾶς ὁ βίος καὶ παίγνιον: ἢ μάθε παίζειν, τὴν σπουδὴν μεταθείς, ἢ φέρε τὰς ὀδύνας → All life is a stage and a play: either learn to play laying your gravity aside, or bear with life's pains.
Latin > French (Gaffiot 2016)
pŏtissĭmus, a, um, sup. de potis, le principal, le plus important, l’essentiel : potissimi libertorum Tac. Ann. 14, 65, les principaux affranchis ; potissima nobilitas Plin. 14, 25, la plus grande notoriété ; potissima causa Tac. Ann. 4, 16, la raison la plus importante.