Sunday: Named after the Sun, Sun-day

Monday: Lundi in French- named after the moon, Moon-day?

Tuesday: Mardi in French- named after Mars, Mars-day

Wednesday: Mercredi in French- named after Mercury, Mercury-day

Thursday: Jeudi in French- named after Jupiter, Jupiter-day

Friday: Vendredi in French- named after Venus, Venus-day

Saturday: Samedi in French- named after Saturn, Saturn-day