cording to John Jamieson's Etymological Dictionary of the Scottish Language (1818),[4] up is used in the sense of something being at an end, and derives from the Old Norse word uppi which is still used in Faroese and Icelandic, while helly refers to a holy day or festival. The Scottish National Dictionary defines helly, probably derived from the Old Norse helgr (helgi in the dative and accusative case, meaning a holiday or festival), as "[a] series of festive days, esp. the period in which Christmas festivities are held from 25th Dec. to 5th Jan.",[5] while aa may represent a', meaning "all".