- (v.t.) To make darker or more intense; to darken; as, the event deepened the prevailing gloom.
- (v.i.) To become deeper; as, the water deepens at every cast of the lead; the plot deepens.
- (v.t.) To make more grave or low in tone; as, to deepen the tones of an organ.
- (v.t.) To make more poignant or affecting; to increase in degree; as, to deepen grief or sorrow.
- (v.t.) To make deep or deeper; to increase the depth of; to sink lower; as, to deepen a well or a channel.
Webster's Revised Unabridged Dictionary
| APA | Webster's. (2011). deepen. Retrieved September 22, 2026, from http://smartdefine.org/deepen/definitions/1995248 |
| Chicago | Webster's. 2011. "deepen" http://smartdefine.org/deepen/definitions/1995248 (accessed September 22, 2026). |
| Harvard | Webster's 2011, deepen, Smart Define, viewed 22 September, 2026, <http://smartdefine.org/deepen/definitions/1995248>. |
| MLA | Webster's. "deepen" 27 May 2011. Web. 22 September 2026. <http://smartdefine.org/deepen/definitions/1995248> |