lough

Etymology 1

Borrowed from Irish loch (from Old Irish loch), from Proto-Celtic *loku (“lake, pool”), from Proto-Indo-European *lókus (“pond, pool”). Doublet of loch and Looe.

noun

1. (Ireland) A lake or long, narrow inlet, especially in Ireland.
   Outside, a freezing wind whips across Belfast lough […]. January 26 2009, Henry McDonald, “It's got fancy flats, a hotel. Even a bank. But can the Titanic Quarter stay afloat?”, in The Guardian

Etymology 2

From Middle English lough, luh, borrowed from Cumbric *luch, derived from Proto-Brythonic *luch, from Proto-Celtic *lokus (“lake, pool”).

noun

1. (Northumbria) lake, pool