Entry 2 senses · 2 variants Webster, 1913 newborn /(nū"bôrn`)/ · new·born · IPA /nˈuːbɔrn/ a. n. 01 a. Recently born. 1. Recently born. 02 n. A baby recently born, usually less than one month old; a neonate. 1. A baby recently born, usually less than one month old; a neonate.