depth

American  

[depth] / dɛpθ /

noun

1. a dimension taken through an object or body of material, usually downward from an upper surface, horizontally inward from an outer surface, or from top to bottom of something regarded as one of several layers.

2. the quality of being deep; deepness.

3. complexity or obscurity, as of a subject.

   a question of great depth.

4. gravity; seriousness.

   I don't think you recognize the depth of the problem.

   Synonyms:

   weight, significance, importance, import

5. emotional profundity.

   the depth of someone's feelings.

6. intensity, as of silence, color, etc.

7. lowness of tonal pitch.

   the depth of a voice.

8. the amount of knowledge, intelligence, wisdom, insight, feeling, etc., present in a person's mind or evident either in some product of the mind, as a learned paper, argument, work of art, etc., or in the person's behavior.

9. a high degree of such knowledge, insight, etc.

10. Often depths a deep part or place.

    from the depths of the ocean.

11. an unfathomable space; abyss.

    the depth of time.

12. Sometimes depths the farthest, innermost, or extreme part or state.

    the depth of space;

    the depths of the forest;

    the depths of despair.

13. Usually depths. a low intellectual or moral condition.

    How could he sink to such depths?

14. the part of greatest intensity, as of night or winter.

15. Sports. the strength of a team in terms of the number and quality of its substitute players.

    With no depth in the infield, an injury to any of the regulars would be costly.

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idioms

1. in depth, extensively or thoroughly.

   Make a survey in depth of the conditions.

2. out of / beyond one's depth,

   1. in water deeper than one's height or too deep for one's safety.

   2. beyond one's knowledge or capability.

      The child is being taught subjects that are beyond his depth.

depth British  

/ dɛpθ /

noun

1. the extent, measurement, or distance downwards, backwards, or inwards

2. the quality of being deep; deepness

3. intensity or profundity of emotion or feeling

4. profundity of moral character; penetration; sagacity; integrity

5. complexity or abstruseness, as of thought or objects of thought

6. intensity, as of silence, colour, etc

7. lowness of pitch

8. nautical the distance from the top of a ship's keel to the top of a particular deck

9. (often plural) a deep, far, inner, or remote part, such as an inaccessible region of a country

10. (often plural) the deepest, most intense, or most severe part

    the depths of winter

11. (usually plural) a low moral state; demoralization

    how could you sink to such depths?

12. (often plural) a vast space or abyss

13. 1. in water deeper than one is tall

    2. beyond the range of one's competence or understanding

14. thoroughly or comprehensively See also in-depth

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depth More Idioms  

1. see in depth; out of one's depth.

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Other Word Forms

• depthless adjective

Etymology

Origin of depth

First recorded in 1350–1400; Middle English depthe, equivalent to deep + -th ¹

Explanation

Depth is the measure of how deep something goes. The swimming pool has a depth of six feet. The well has an unknown depth. People can be deep as well—you know by looking at some people that they have depth. Depth goes with other measure words that end in "th." Length is how long something is. Breadth is how wide or broad. The expression "plumb the depths" means to take a measure of how deep something goes. Depth also can mean deepness—your English teacher might instruct you to write papers with depth.

Example Sentences

It’s also a top-heavy draft, with a ton of depth in the first round and no clear first overall pick.

From Los Angeles Times • Apr. 12, 2026

Then, a series of leaked audio transcripts released last week appeared to expose the depth of the ties between Orbán’s government and Russia.

From The Wall Street Journal • Apr. 12, 2026

Pine nuts go in next, toasted until they’re pale gold and rich, adding a quiet, nutty depth.

From Salon • Apr. 10, 2026

The hosts' strength in depth from the bench proved the difference in the second period as Northampton could only manage two penalties.

From BBC • Apr. 10, 2026

I stopped thinking about the darkness and depth when I looked up into the night sky.

From "The Line Tender" by Kate Allen

Related Words

• acumen
• intellect
• intelligence
• sense