IPA: /ˈɪmpətənt/
KK: /ˈɪmpətənt/
Not able to perform sexual intercourse or lacking power to act effectively; weak or helpless.
He felt impotent in the face of the overwhelming challenges.
Impotent → It is formed from "in-" (meaning not) and "potent" (from Latin "potens", meaning powerful or able). The word "impotent" means not able or lacking power.
Think of 'not' ('in-') being combined with 'powerful' ('potent') — that's why impotent means lacking power.