From OE 'flōwan,' from PIE *plew- (to flow) — one of the oldest water-words in English, kin to 'flood' and Latin 'pluere' (to rain).
To move along or out steadily and continuously in a current or stream; to circulate or proceed smoothly.
From Old English "flōwan" ("to flow, to stream, to issue"), from Proto-Germanic *flōaną ("to flow"), tracing to Proto-Indo-European *plew- ("to flow, to swim, to float"). This PIE root is exceptionally prolific: it produced Greek "πλέω" (pléō, "I sail, I swim"), Latin "pluere" ("to rain," whence English "pluvial"), Sanskrit "plávate" ("he swims, he floats"), and Lithuanian "plūsti" ("to float"). In the Germanic branch, *plōw- with characteristic loss of initial p- yielded Old English "flōwan," Old