mainspringEnglish → FrenchOxford English–Frenchmainspring /BrE ˈmeɪnsprɪŋ , AmE ˈmeɪnˌsprɪŋ / noun 1 figurative (pivotal element) (of action, plot) ressort m (of de); (of life) raison f (of de) 2 (of watch) ressort m