The main island of Dønna is connected to the neighboring Herøy Municipality to the south by the Åkviksundet Bridge.

The name is probably derived from the Old Norse verb dynja which means to "rumble" or "roar" (referring to the swell of the waves on the island).

The official blazon is "Or a schnecke azure from base sinister to dexter" (Norwegian: Delt av gull og blått ved virvelsnitt).

This means the arms have a field (background) that is divided by a line called a schnecke (a swirling clockwise spiral design that is looks like a wave).

The field located above the line has a tincture of Or which means it is commonly colored yellow, but if it is made out of metal, then gold is used.

The arms are a canting symbol for the municipality since the Norwegian word dønning means "wave" or "swell".

The highest point in the municipality is the 855.1-metre (2,805 ft) tall mountain Dønnmannen on the island of Dønna.