About the Marchessault surname
The surname Marchessault has an onomastic interpretation that still needs to be placed in the history of each family line. The form of Marchessault is compatible with French surname tradition. It may derive from an old given name, a place, a nickname, an occupation, or a regional variant; the historical form of the family line is needed to distinguish between these possibilities. This interpretation helps explain the formation of the surname without establishing the origin of any particular family line. The etymological interpretation should be compared with the earliest spellings and places associated with each family line.
Pronunciation:
Mar-chè-so/maʁʃɛso/