Words and Proper Names

traig

2974.
Hamp (Eric P.): *-og- in British Celtic and notes on bro.
In ÉtC 19 (1982), pp. 143–149.
II. Welsh troed, Breton troad, OIr. droch: Suggests that OIr. droch and traig are two different agent nouns derived from the PIE root *dhregh- ‘run’.