illegitimate

1. Not sanctioned by marriage.Examples: "She had only to collect her memories, which proved to her that “anybody” regarded the illegitimate children as more rightfully to be looked shy on and deprived of social advantages than illegitimate fathers."; "I heard last night that a what-do-you-call it?—claimant?—has arrived who says Pat Wayne is his illegitimate father."dated

2. (botany) Involving the fertilization of pistils by stamens not of their own length, in heterogonously dimorphic and trimorphic flowers.Examples: "illegitimate union; illegitimate fertilization"; "[…] the legitimate unions between the two forms of the above nine species of Primula are much more fertile than the illegitimate unions; although in the latter case pollen was always taken from a distinct plant of the same form."