Nouns

(n)depth, deepnessthe extent downward or backward or inward“the depth of the water”, “depth of a shelf”, “depth of a closet”
(n)depthdegree of psychological or intellectual profundity
(n)depth(usually plural) a low moral state“he had sunk to the depths of addiction”
(n)astuteness, profundity, profoundness, depth, deepnessthe intellectual ability to penetrate deeply into ideas
(n)depththe attribute or quality of being deep, strong, or intense“the depth of his breathing”, “the depth of his sighs”, “the depth of his emotion”