flow
To move steadily and continuously in a current or stream.
Etymology
From Old English flōwan (to flow), from Proto-Germanic *flōaną, from PIE *plew- (to flow, to swim). The PIE *p- regularly became *f- in Proto-Germanic by Grimm's Law. The same root gave Latin pluere (to rain), Greek plein (to sail), and English flood, fly, and fleet.
The Journey: *plew- → flow
*plew-
*flōaną
flōwan
flow
Cognates Across Languages
These words in other languages descend from the same PIE root *plew-. They are not borrowings but independent inheritances from a common ancestor.
| Language | Word |
|---|---|
| Greek | plein (πλεῖν) — to sail |
| Latin | pluere — to rain |
| German | fließen — to flow |
| Lithuanian | plūsti — to float |
Did You Know?
Flow, flood, fly, fleet, and float all descend from PIE *plew-. The common thread is motion through a medium — water or air. Even the word pluvial (rainy) comes from the Latin branch of the same root.
This word descends from the Proto-Indo-European root *plew-. See the full root page for descendant trees, sound law references, and scholarly discussion.