View Message

O Corrain & Maguire's Irish Names says that Dunlaith perhaps meant "lady of the fortress." The earliest Dunlaith was a daughter of a warrior in Connacht. Dunlaith was also the name of the wife of the "high king" Niall Frassach in the 8th century A.D.

The laith part could mean Princess or Lady if you compare it to names like GORMLAITH and ÓRFHLAITH
The Dun part could be brown, I have seen this name on another site being given the meaning brown lady

I would guess it comes from dún meaning "fort" and flaith meaning "princess". It would be pronounced DOON-lah. So "princess of the fort" is a possible (probable?) meaning. It's a rare name in Ireland, I've never seen it used before.