Isidore de Séville , Origines (Etymologiarum), 11.1.102

dicuntur autem ista et inhonesta , quia non habent eam speciem decoris sicut membra quae in promptu locata sun
Bibliography
J. N. Adams , The Latin Sexual Vocabulary, 56 - More with this book More on this page
Tags
#aidoion #euphemism #male #mentula