Welsh ceffyl

← Breton kefel (cognate)

← Proto-Brythonic *kėfɨl (inherited)

← Proto-Celtic *kapallos (inherited)

← Proto-Celtic *kaballos (mention)

← Middle Welsh keffyl (inherited)

→ Welsh cyffylog (suffix)

→ Irish capall (cognate)

→ Scottish Gaelic capall (cognate)

→ Old Irish capall (cognate)