/ Dictionary / Index L lough: Meaning and Definition of Find definitions for: lough Pronunciation: (lok, lokh), [key] — n. Irish Eng. a lake. a partially landlocked or protected bay; a narrow arm of the sea. Cf. loch. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: lough (Thesaurus) Lou Gehrig's disease Lough Neagh Related Content Daily Word Quiz: tenacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language