Old Irish sír

← Breton hir (cognate)

← Proto-Celtic *sīros (inherited)

← Welsh hir (cognate)

← Cornish hyr (cognate)

→ Irish sia (inherited)

→ Irish sín (cognate)

→ Irish síor- (derived)

→ Irish síoraí (mention)

→ Scottish Gaelic sìor (inherited)

→ Manx sheer- (inherited)

→ Latin serus (cognate)

→ Middle Irish sínid (cognate)