#1 deepen v. [intensify, compound, heighten] make more intense, stronger, or more marked; "The efforts were intensified", "Her rudeness intensified his dislike for her"; "Pot smokers claim it heightens their awareness"; "This event only deepened my convictions". wn
#2 deepen v. [intensify] become more intense; "The debate intensified"; "His dislike for raw fish only deepened in Japan". wn
#3 deepen v. make deeper; "They deepened the lake so that bigger pleasure boats could use it". wn
#4 deepen v. [change] become deeper in tone; "His voice began to change when he was 12 years old"; "Her voice deepened when she whispered the password". wn
vizzz