What is Adulterine?

Legal Definition
A term used in the civil law to denote the issue of an adulterous intercourse. See Nicholas on Adulterine Bastardy.
-- Bouviers Law Dictionary
Legal Definition
Begotten in an adulterous intercourse. In the Roman and canon law, adulterine bastards were distinguished from such as were the issue of two unmarried persons, and the former were treated with more severity, not being allowed the status of natural children, and being ineligible to holy orders.
-- Black's Law Dictionary
Legal Definition
A child born of adulterous intercourse.
-- Ballentine's Law Dictionary