Don't know what the argument is about the derivation of the word shanty (preferred in OED; chantey or chanty in the American Merriam Webster dictionary). In the OED it is "said" to come from Fr. chantez but that is an opinion. Our word chant came from Middle English chaunten which came from Middle French chanter which came from Latin cantare. Shanty-chantey obviously fits somewhere in here. The first printed use of chantey-shanty is mid-19th Century but the word could be much older; chant goes back to the 1300's or so. What is the point here? A shanty-chantey is defined as a "sailors song, esp.one sung during heavy work." Word definitions are shifting all the time; you may try to fix them in stone but sooner or later the stone will erode. Obviously some of us would extend the meaning, and in time could become the majority. In an earlier thread someone made the point that work songs of this type were older than the stated first use of the word, regardless of what they were called.