Fill in the response. Convo:
[x]. What are the more unusual island names?
[y]. There are also examples of island names that were originally Gaelic but have become completely replaced.
[x]. Any examples?
[y]. For example, Adomnán records "Sainea", "Elena", "Ommon" and "Oideacha" in the Inner Hebrides, which are of unknown location and these names must have passed out of usage in the Norse era.
[x]. Are there any other interesting aspects about this article?
[y]. One of the complexities is that an island such as Rona may have had a Celtic name, that was replaced by a similar-sounding Norse name, but then reverted to an essentially Gaelic name with a Norse ending.
[x]. Why did they settle on these names?
[y]. In the context of the Northern Isles it should be borne in mind that Old Norse is a dead language and that as a result names of Old Norse origin exist only as loan words in the Scots language.
[x]. Do any of the islands still have that name?
[y]. Nonetheless if we distinguish between names of obviously Norse origin and those with a significant Scots element the great majority are in the former camp.
[x]. What are some others?
[y]. 
"Muckle", meaning large or big, is one of few Scots words in the island names of the "Nordreyar" and appears in Muckle Roe and Muckle Flugga in Shetland and Muckle Green Holm and Muckle Skerry in Orkney.