Welsh heddiw

← Breton hiziv (cognate)

← Breton hiziw (mention)

← Proto-Celtic *so (derived)

← Proto-Celtic *dīyos (mention)

← Cornish hethew (cognate)

← Latin hodie (cognate)

← Middle Breton hizio (cognate)

→ Breton hiziv (cognate)

→ Welsh eleni (mention)