Arnamul is a stack

Stack (geology)

A stack is a geological landform consisting of a steep and often vertical column or columns of rock in the sea near a coast, isolated by erosion. Stacks are formed through processes of coastal geomorphology, which are entirely natural. Time, wind and water are the only factors involved in the...

 off the west coast of Mingulay

Mingulay

Mingulay is the second largest of the Bishop's Isles in the Outer Hebrides of Scotland. Located south of Barra, it is known for its important seabird populations, including puffins, Black-legged Kittiwakes, and razorbills, which nest in the sea-cliffs, amongst the highest in the British...

 in the Western Isles, Scotland

Scotland

Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

. Although precipitous, sheep were grazed on its relatively flat summit during the human occupation of Mingulay.

Haswell-Smith (2004) states that the name means "erne mound". Mac an Tailleir (2003) does not provide a derivation, although he quotes "Arnabol" as meaning "eagle farm" or "Arne's farm" from the Norse

Old Norse

Old Norse is a North Germanic language that was spoken by inhabitants of Scandinavia and inhabitants of their overseas settlements during the Viking Age, until about 1300....

.