(pathology) A potentially painful or harmful medical condition in which the erect penis (erection) does not return to its flaccid state (despite the absence of both physical and psychological stimulation), often as a result of a spinal injury.
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Lana: [searching Cecil's pants for his car keys, suddenly stops] eww, son of a ...
Cecil Vandertunt: I'm priapic from the shock!
Lana: Shock doesn't cause priapisms!
Adam Reed. Archer, season 8, Dreamland: Gramery, Halberd! (2017)
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His ass was prancing and making after the elephants, gaping and martially braying, as it were to sound a charge, as he did when formerly in the Bacchanalian feasts he waked the nymph Lottis, when Priapus, full of priapism, had a mind to priapize while the pretty creature was taking a nap.