society > society and the community > kinship or relationship > marriage or wedlock > types of marriage custom or practice > [adjective] > relating to or practising concubinage (4)
in (also of, on) purchasea1400
in (also of, on) purchase: in concubinage; out of wedlock. Obsolete (Scottish in later use).
concubinary1570
Relating to concubinage; (of persons) living in, or sprung from, concubinage.