French épais

← Middle French espés (inherited)

← Old French espés (inherited)

← Proto-Indo-European *spidtos (inherited)

← Latin spissus (inherited)

→ Catalan espès (cognate)

→ Spanish espeso (cognate)

→ French épaissir (suffix)

→ French épaissement (suffix)

→ Haitian Creole epè (derived)

→ Italian spesso (cognate)