Etymology
Advertisement

hard-on (n.)

"penile erection," 1922, earlier as an adjective (1893), from hard + on.

updated on October 10, 2017

Advertisement
Advertisement
Definitions of hard-on from WordNet

hard-on (n.)
an erect penis;
Synonyms: erection
Etymologies are not definitions. From wordnet.princeton.edu, not affiliated with etymonline.