Translation according to P. W. Joyce:
Breandrum in Galway, stinking drum or hill-ridge. For Brian, stinking, and its compounds, see [reproduced below] vol. ii.p. 397.
Bréan, which signifies putrid, foul, fetid, or stinking, is often applied to spots that omit an offensive smell. There are various circumstances that may originate foul smelling exhalations from land. One of the indications that led Colonel Hall to the discovery of copper mines at Glandore in Cork, was the fetid smell emitted from a fire of turf cut in a neighbouring bog, which turned out to be strongly impregnated with copper; this bog was known as the "stinking bog" (móin bhréan); and the people had it that neither cat nor dog could live in the house where the turf was burnt. There is a place called Brenter in the parish of Inver, east of Killybegs in Donegal, whose name is in Irish Bréan-tír, stinking district; and it got this name from the strong sulphureous smell of a spa which is in the townland. There was a celebrated district of the same name lying north-east of Mount Callan in Clare, which is often mentioned in the annals (always as Brentir), but I do not know why it was so called. In most cases places with names of this kind are swamps, pits, or bogs, which emit foul odours from decaying animal or vegetable matter. There are ten townlands in various counties, called Breandrum, stinking ridge.