Pronunciation: (val'ē),[key] —n., —pl.-leys. 1. an elongated depression between uplands, hills, or mountains, esp. one following the course of a stream.
2. an extensive, more or less flat, and relatively low region drained by a great river system.
3. any depression or hollow resembling a valley.
4. a low point or interval in any process, representation, or situation.
5. any place, period, or situation that is filled with fear, gloom, foreboding, or the like: the valley of despair. 6. Archit.a depression or angle formed by the meeting of two inclined sides of a roof.
7. the lower phase of a horizontal wave motion.