A small, narrow, secluded valley. A depression between hills; See examples of glen used in a sentence. Collins cobuild advanced learner’s dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. A deep, narrow valley, especially among…. A deep, narrow valley, especially among mountains: Definition of glen noun in oxford advanced learners dictionary. Glen (ɡlɛn) n (physical geography) a narrow and deep mountain valley, esp in scotland or ireland [c15: From scottish gaelic gleann, from old irish glend] Many place-names in scotland with glen derive from the gaelic gleann (deep valley), with some being from the cognates in the brittonic languages cumbric and pictish or from the … Accessed 30 sep. A glen is a deep, narrow valley, especially in the mountains of scotland or ireland. · glen (plural glens) a secluded and narrow valley, especially one with a river running through it; Sea eagle chicks will soon be soaring over the glens. Glen, n. ¹ meanings, etymology, pronunciation and more in the oxford english dictionary · glenn is typically a given name, while glen refers to a narrow valley, especially in mountainous or wooded areas.