| 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. | Architecture. a depression or angle formed by the meeting of two inclined sides of a roof. |
| 7. | the lower phase of a horizontal wave motion. |
