■ noun
1》 the distance from the top or surface to the bottom of something or to a specified point within it.
↘the distance from the front to the back of something.
↘the apparent existence of three dimensions in a two-dimensional representation.
2》 the quality of being intense or extreme.
↘complexity and profundity of thought.
↘comprehensiveness of study or detail: third-year courses go into more ~.
3》 ( the ~s ) the deepest or lowest part of something.
Phrases
hidden ~s previously unnoticed qualities.
in ~ in great detail; comprehensively and thoroughly.
out of one's ~
1》 in water too deep to stand in.
2》 in a situation beyond one's capabilities.
Origin
ME: from deep + -th 2 , on the pattern of pairs such as long , length .