←
Proto-Celtic *-ākos (inherited)
←
Scottish Gaelic -ag (doublet)
←
Proto-Indo-European *-eh₂- (mention)
←
Proto-Indo-European *-kos (mention)
←
Proto-Indo-European *-ḱos (mention)
←
Old Irish -ach (inherited)
→
Scottish Gaelic salach (affix)
→
Scottish Gaelic -ag (doublet)
→
Scottish Gaelic bacach (affix)