Berthelot Family History
Berthelot Surname Meaning
French and Breton: from a French pet form of any of various personal names based on the ancient Germanic element berht ‘bright famous’ for example Bert(h)aud (see Berteau).
Possibly also from a French pet form of the personal name Barthélemy (see Bartholomew) or its variant Berthélemy.
In France the surname Berthelot is most common in Brittany.
Source: Dictionary of American Family Names 2nd edition, 2022