Old Irish trén

← Breton trec'h (cognate)

← Gaulish Trexius (cognate)

← Gaulish Trexa (mention)

← Gaulish Trenus (mention)

← Proto-Celtic *trexsnos (inherited)

← Proto-Celtic *trexsos (mention)

← Proto-Indo-European *(s)treg- (derived)

← Cornish trygh (cognate)

← Old Norse þróttr (cognate)

← Primitive Irish ᚈᚈᚏᚓᚅᚐᚂᚒᚌᚑᚄ (cognate)

← Primitive Irish ᚈᚏᚓᚅᚐᚌᚒᚄᚒ (mention)

← Middle Welsh trech (cognate)

→ Breton trec'h (cognate)

→ Irish aintréan (mention)

→ Scottish Gaelic treun (inherited)