1 a powerless; lacking all strength. b helpless, decrepit.
2 (esp. of a male) unable, esp. for a prolonged period, to achieve a sexual erection or orgasm.
Derivatives:
impotence n. impotency n. impotently adv.
Etymology: ME f. OF f. L impotens (as IN-(1), POTENT(1))
Useful english dictionary. 2012.