† ˈpuissancyObs.rare. [f. as prec. + -ancy.] The quality of being powerful; power, potency. 1562W. Bullein Bulwark, Bk. Simples 23 b, Some greater, and of more puissancie.1607Topsell Four-f. Beasts 312 Alexander..had neuer bin deliuered aliue, but for the puisancy of his horsse.