Belfast: The Name

The name Belfast is derived from the Irish Béal Feirsde, which was later spelled Béal Feirste.The word béal means "mouth" or "rivermouth" while feirsde/feirste is the genitive singular of fearsaid and refers to a sandbar or tidal ford across a river's mouth.The name would thus translate literally as "(river) mouth of the sandbar" or "(river) mouth of the ford". This sandbar was formed at the confluence of two rivers at what is now Donegall Quay: the Lagan, which flows into Belfast Lough, and its tributary the Farset. This area was the hub around which the original settlement developed. The Irish name Béal Feirste is shared by a townland in County Mayo, whose name has been anglicised as Belfarsad.

An alternative interpretation of the name is "mouth of [the river] of the sandbar", an allusion to the River Farset, which flows into the Lagan where the sandbar was located. This interpretation was favoured by Edmund Hogan and John O'Donovan. It seems clear, however, that the river itself was also named after the tidal crossing.

In Ulster Scots the name of the city is Bilfawst or Bilfaust, although "Belfast" is also used.