Reflux
/ˈriː.flʌks/noun
The backward flow of a fluid or substance; in medicine, the return of stomach acid into the esophagus.
Did you know?Reflux comes from Latin re- (“back”) + fluxus (“flow, stream”), from the same root that gave English flux, fluent, and fluent-like ideas of continuous motion.
Etymological Timeline
Proto-Indo-European
PIE
*pleu-
“to flow, swim”
Latin
Latin
flūxus
“flow, stream, outflow”
Latin
Latin
re- + flūxus
“flowing back”
Late Latin
Latin
refluxus
“a flowing back, ebb”
14th Century
English
reflux
“a flowing back; return flow”
Modern English
English
reflux
“backward flow, especially of stomach acid”
Explore more surprising origins