Entry 2 senses · 2 variants Webster, 1913 Acescent · A·ces·cent · IPA /əˈsiːsənt/ a. n. 01 a. Turning sour; readily becoming tart or acid; slightly sour. 1. Turning sour; readily becoming tart or acid; slightly sour. 02 n. A substance liable to become sour. 1. A substance liable to become sour.