Where does “deugeiniau” come from?
deugeiniau (Welsh) comes from Welsh deugain, from Welsh ugain, from Old Welsh uceint, from Proto-Brythonic ʉgėnt, from Proto-Celtic wikantī, from Proto-Indo-European h₁wih₁ḱm̥t, from Proto-Indo-European dwi(h₁)dḱm̥ti — two tens; two decades; twenty; two-ten.
deugeiniau (Welsh): forties
Ancestry of “deugeiniau”, step by step