The story
- Proto-Brythonic · derived from*tes“heat”
- Old English · inherited from*Tēs(e)
- English todayTees
From Old English *Tēs(e), but uncertain beyond that. Possibly from Proto-Brythonic *tes (“heat”), which would be in reference to the “boiling” surging water of so much of the upper river, especially at places like Cauldron Snout.
Etymology from Wiktionary, CC BY-SA 4.0.