| v. t. | 1. | To make deep or deeper; to increase the depth of; to sink lower; |
| 2. | To make darker or more intense; to darken; | |
| 3. | To make more poignant or affecting; to increase in degree; | |
| 4. | To make more grave or low in tone; | |
| v. i. | 1. | To become deeper; |
| Verb | 1. | deepen - make more intense, stronger, or more marked; "The efforts were intensified", "Her rudeness intensified his dislike for her"; "Potsmokers claim it heightens their awareness"; "This event only deepened my convictions" |
| 2. | deepen - become more intense; "The debate intensified"; "His dislike for raw fish only deepened in Japan" Synonyms: intensify | |
| 3. | deepen - make deeper; "They deepened the lake so that bigger pleasure boats could use it" | |
| 4. | deepen - become deeper in tone; "His voice began to change when he was 12 years old"; "Her voice deepened when she whispered the password" Synonyms: change |