French caillou

← Gaulish cala (mention)

← Dutch kei (cognate)

← Norman caillou (mention)

← Picard cailleu (cognate)

← Walloon caie (cognate)

→ English Caillou (mention)

→ French caillouter (suffix)

→ Galician callao (cognate)

→ Galician callau (cognate)

→ Occitan acalhaudar (mention)