Entry 1 sense Webster, 1913 Quintessential /kwĭnˌ-tĭs-ĕn'-shəl/ · Quin·tes·sen·tial · IPA /ˌkwɪntɪˈsɛnʃəl/ 01 a. Of the nature of a quintessence; purest; most characteristic. 1. Of the nature of a quintessence; purest; most characteristic.