Where does “*trọstr” come from?

*trọstr (Proto-Brythonic) comes from Latin transtrum, from Latin trāns, from Latin Padus, from Lepontic Bodincus, from Proto-Indo-European bʰudʰmḗn, from Proto-Indo-European dʰewbʰ-, from Proto-Indo-European dʰewh₂- — smoke; mist, haze.

Ancestry of “*trọstr”, step by step

Step	Language	Word	Meaning
1	Latin	transtrum	crossbeam, transom; thwart of a vessel
2	Latin	trāns	across, beyond
3	Latin	Padus	the River Po
4	Lepontic	Bodincus	—
5	Proto-Indo-European	bʰudʰmḗn	bottom
6	Proto-Indo-European	dʰewbʰ-	deep
7	Proto-Indo-European	dʰewh₂-	smoke; mist, haze

Words derived from “*trọstr”

trawst
trawst

Every word from Proto-Indo-European dʰewh₂- →Every word from Proto-Indo-European dʰewbʰ- →Every word from Proto-Indo-European bʰudʰmḗn →