Proto-Celtic *betwiyos

→ Catalan beç (derived)

→ Catalan bedoll (derived)

→ Welsh bedw (inherited)

→ Spanish abedul (derived)

→ Old French boul (derived)

→ Irish beith (inherited)

→ Scottish Gaelic beith (inherited)

→ Italian betulla (derived)

→ Latin betula (derived)

→ Occitan beç (derived)

→ Portuguese bétula (derived)