Learner's definition of DEPTH
1 a : a distance below a surface
These fish typically live at depths of 500 feet or more.
Students will test the temperature of the water at different/varying/various depths.
The boat sank to a depth of several hundred feet.
measuring the depth of the water/river/sea
the depth of a hole
The pool has a depth of 12 feet.
[noncount] b [count] : the distance from the front of something to the back — usually singular
Measure the height, width, and depth of the cabinet.
The bench's depth is 22 inches.
2 [count] : an area that exists far below a surface or far inside something : a deep place or area — usually plural
— often used figuratively
They disappeared into the depths of the forest.
Scientists have begun using the machine to explore the ocean depths.
the black depths of outer space
The actress must examine her own emotional depths to perform the role successfully.
Around midnight, a loud noise woke us from the depths of sleep.
I knew in the depths of my heart/soul/being [=I believed very strongly] that we would survive.
The memory lies hidden in the depths of her mind. [=she has not thought about the memory in a long time]
in the depths of winter [=in the middle of winter; in the coldest part of winter]
3 a : a very low or bad state or condition — usually plural
b : the worst part of something
After losing his job, he sank into the depths of misery/despair/depression.
The film portrays a family's difficult climb from the depths of poverty.
I can't believe he lied. He's really sunk to new depths.
The team is reaching/plumbing new depths this season. [=the team is playing worse than it ever has before]
4 [noncount] : the quality of being deep: such as a : the quality of being strongly felt
b : the quality of being very bad or serious c : the quality of being complete or thorough d : the quality of being strong in color, taste, etc. e : the quality of being low in sound f US, sports : the quality of having many good players on a team
We were surprised by the depth of her anger/pain/shame.
He wanted to express the depth of his love for her.
No one doubted the depth of his faith. [=they all knew that his faith was strong]
the depth of her commitment to the project
The dancers expressed great depth of feeling/emotion.
: in a thorough or complete way
out of your depthalsobeyond your depth
1 : dealing with a situation or subject that is too difficult for you 2 chiefly British : in water that is deeper than your height