This is the worst headache I've ever had, so I'm going to need an especially potent pain-killer.
omnis (all, every)#potis (powerful, able, capable) (Latin)
He is very POTENTial. means very influential. i.e. powerful Remember Impotent? Which means weak and ineffective. Potent which means- powerful and influential, is the antonym of Impotent. As a mnemonics of Impotent we used: a person who is IMPOTENT/Powerless is not treated as IMPORTANT