Such charges can be dropped (5)

I believe the answer is:

depth

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'such charges can' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for depth that I've seen before include "Distance downwards" , "Intensity (of emotion)" , "Insight" , "Deepness" , "Measurement from front to back" .)

I've seen this clue in the Evening Standard.

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