Monday is made up from Old English mona (moon) and daeg (day) meaning “moon day” or “day of the moon”. As a surname, Monday comes from Old Norse given name Mundi via mundr meaning “protection, protector” though it could also have originated as a nickname for someone who had a particular association on that day. As an Irish surname, Monday is an anglicized form of Gaelic Mac Giolla Eoin meaning “son of the servant of Eoin”, the latter coming about as a confusion of Irish Luain meaning “Monday”. According to a nursery rhyme titled “Monday’s Child” (which is about the seven days of the week), Monday’s child is fair of face.
- Mondae (English)