Reaney &
Wilson's
A Dictionary of English Surnames says that in medieval times
Drew was primarily from
Drogo, a Germanic name of Frankish origin, probably meaning "ghost, phantom", and becoming in French Drues, Dru, Driu, etc. They then say "
Drew was also a pet form of Andrew, which was confused with the French . In 1400, Drew Barentyn appealed to the Council to correct his christian name to Drew in the list of freemen of the city, where it had been incorrectly listed as Andrew."