reflux

UK: /ˈriːflʌks/ US: (rē′fluks′)

WordReference Random House Unabridged Dictionary of American English © 2026

re•flux  (rē′fluks′), n. 

1. a flowing back;
   ebb.

• Medieval Latin refluxus. See re-, flux
• late Middle English 1400–50

Collins Concise English Dictionary © HarperCollins Publishers::

reflux / ˈriːflʌks/ verb

1. to boil or be boiled in a vessel attached to a condenser, so that the vapour condenses and flows back into the vessel

noun

1. an act of refluxing
2. (as modifier): a reflux condenser
3. the act or an instance of flowing back; ebb

Etymology: 15th Century: from Medieval Latin refluxus, from Latin refluere to flow back