CONTUBERNIUM, civ. law. As among the Romans, slaves had no civil state, 
their marriages, although valid according to natural law, when contr acted 
with the consent of their masters, and when there was no legal bar to them, 
yet were without civil effects; they having none except what arose from 
natural law; a marriage of this kind was called contubernium. It was so 
called whether both or only one of the parties was a slave. Poth. Contr. de 
Mariage, part 1, c. 2, Sec. 4. Vicat, ad verb.