This is the 44th most frequent Icelandic word.
vestmannaeyjum
"Vestmannaeyjum" means "Westman Islands," an archipelago off the south coast of Iceland.
Here, 'Vestmannaeyjar' is used as the name of a location, specifically the Westman Islands in Iceland.
Ég heimsótti Vestmannaeyjar síðasta sumar.
I visited the Westman Islands last summer.
'Vestmannaeyjum' appears in its dative plural form, signifying the location context within the sentence.
Við skelltum í alvöru partý í Vestmannaeyjum.
We threw a real party in the Westman Islands.
Here, 'Vestmannaeyjum' in the dative plural form indicates the place where the horses are located.