priapism n.

"phallic; of or relating to the cult and myths of Priapus," 1786, with -ic + Priapus (Greek Priapos), son of Dionysus and Aphrodite, the god who personified male reproductive power. His name is of unknown origin. Earlier was Priapean (1690s).

word-forming element making nouns implying a practice, system, doctrine, etc., from French -isme or directly from Latin -isma, -ismus (source also of Italian, Spanish -ismo, Dutch, German -ismus), from Greek -ismos, noun ending signifying the practice or teaching of a thing, from the stem of verbs in -izein, a verb-forming element denoting the doing of the noun or adjective to which it is attached. For distinction of use, see -ity. The related Greek suffix -isma(t)- affects some forms.

"excessive and unrestrainable venereal desire in the male," 1650s, medical Latin, from Greek satyriasis, from satyros (see satyr). Also in the same sense was satyromania (1889 as a dictionary word; 1759 in Modern Latin), and compare priapism.