†aˈbastard,v.Obs.[ad.Fr.abastardir (as old as 12th c.) from àprep.+ bastard.Cf.OSp. abastardar.]prop.To make or declare bastard or illegitimate: hence, to make spurious or degenerate; to debase, corrupt, deteriorate.1610DonnePseudo-Martyr 226. §6In some of the meane Parents by the way there may be fallacies which may corrupt & Abastard it.1651Life of Father Sarpi 86 (1676)They further insinuated that the Roman Religion was insensibly abastarded.