noun Old English Law.
the first-born illegitimate son of parents whose second son was legitimate.
Compare mulier puisne.
Origin of bastard eigne
1580–90; eigne < Anglo-French: elder, Old French ainsné (ainz before (< Vulgar Latin *antius, for Latin anteā) + ne born; see nee)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019