shellbacks From WikiWord, the free dictionary English Contents DefinitionsRelated wordsReferences DefinitionsnounA worldly sailor.A sailor who has crossed the equator. Related wordsSynonymsbarnacleshellsturtlebackshell jacketshellbarkshinersseashellsshellacshellfirebluebackseashellleatherjacketssoftshellkickshawsturtle shellschoonerscockleshell References Wiktionary — shellbacks Wikipedia — shellbacks