Entry 2 senses · 2 variants Webster, 1913 Nonessential /nänˌ-ĭs-ĕn'-shəl/ · Non·es·sen·tial · IPA /nˌɑnɪsˈɛnʃəl/ a. n. 01 a. Not essential. 1. Not essential. 02 n. A thing not essential. 1. A thing not essential.