From Greek: ἑρμῆς. In ancient Greek and Roman sculpture, a statue with a head, and sometimes a torso, above a squared pedestal, with male genitals often sculpted on the pedestal at the appropriate height. Web resource here.
Attributed to the workshop of Boëthos of Kalchedon. Herm of Dionysos. Bronze and calcitic stone. Ca. 200 – 100 BCE. J. Paul Getty Museum, Villa Collection, Malibu, California.