Entry 2 senses · 2 variants Webster, 1913 Outflow /out'-flōˌ/ · Out·flow · IPA /ˈaʊtflˌoʊ/ n. v. i. 01 n. A flowing out; efflux. 1. A flowing out; efflux. 02 v. i. To flow out. 1. To flow out.