Old Irish fuil

← Proto-Celtic *wolis (inherited)

← Proto-Indo-European *welh₃- (derived(sga/mga))

← Proto-Indo-European *welh₃- (root)

← Proto-Indo-European *welh₃- (derived)

→ Irish fuil (inherited)

→ Scottish Gaelic fuil (inherited)

→ Manx fuill (inherited)

→ Middle Irish fuil (inherited)

→ Old Irish fuilech (affix)

→ Old Irish fuilide (suffix)