Entry 2 senses · 2 variants Webster, 1913 Reflux /(r?"fl?ks`)/ · Re·flux · IPA /ˈɹiː.flʌks/ a. n. 01 a. Returning, or flowing back; reflex; as, reflux action. 1. Returning, or flowing back; reflex; as, reflux action. 02 n. A flowing back, as the return of a fluid; ebb; reaction; as, the flux and reflux of the tides. 1. A flowing back, as the return of a fluid; ebb; reaction; as, the flux and reflux of the tides. “All from me Shall with a fierce reflux on me redound.” — Milton.