Je me culture avec l’interwebz : Sea Shanty, ou chanty, ou chantey, viendrait du français « chanter ».
Sea shanty - Wikipedia
▻https://en.wikipedia.org/wiki/Sea_shanty
The origin of the word “shanty” is unknown, though several inconclusive theories have been put forth.[3] One of the earliest and most consistently offered derivations is from the French chanter, “to sing.”[4]