Old Irish oss-

← Proto-Celtic *uss- (inherited)

← Proto-Indo-European *[[úd]]-s- (derived)

→ Irish díbir (affix)

→ Old Irish turcbál (affix)

→ Old Irish fofúasna (affix)

→ Old Irish adopair (affix)

→ Old Irish doróscai (affix)

→ Old Irish indocbál (affix)

→ Old Irish toschith (affix)

→ Old Irish doinóla (affix)

→ Old Irish conutaing (affix)

→ Old Irish indárban (affix)

→ Old Irish comthururas (affix)

→ Old Irish díummusach (affix)

→ Old Irish conúalai (affix)

→ Old Irish dodúrig (affix)

→ Old Irish dodíuschi (affix)

→ Old Irish doinmlig (affix)

→ Old Irish dofúarat (affix)

→ Old Irish conoscaigi (affix)

→ Old Irish conosna (affix)