εὐμήχανον

From LSJ

ὥσπερ ἀνέµου 'ξαίφνης ἀσελγοῦς γενοµένου → just as when a wind suddenly turns foul, just as when a wind suddenly turns nasty

Source

Russian (Dvoretsky)

εὐμήχᾰνον: τό Plut. = εὐμηχανία.