From Latin 'virtus' (manliness, valor), from 'vir' (man) — gradually universalized into moral goodness.
Moral excellence and righteousness; a particular good quality or habit; the efficacy or power of something.
From Old French 'vertu,' from Latin 'virtūs' meaning 'manliness, valor, moral strength, excellence,' from 'vir' (man, male person), from PIE *wiHrós (man). The word originally denoted the qualities that defined an ideal Roman male — courage, strength, and moral seriousness — before broadening to encompass any form of moral excellence regardless of gender. Cicero extended 'virtūs' to cover all four cardinal
The word 'virtue' literally means 'manliness' — from Latin 'vir' (man), the same root that gives us 'virile.' Old English had its own cognate 'wer' (man), now extinct except in 'werewolf' (man-wolf). That a word meaning 'manliness' became the universal term for moral excellence regardless of gender is one of the language