A waste product rococo art used this to depict? (6)

I believe the answer is:

cowpat

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'a waste product rococo art used this to depict?' is the definition.
The definition suggests a singular noun which matches the answer.

This is the entire clue.

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(Other definitions for cowpat that I've seen before include "Bovine dung" , "You don't want to put your foot in it" , "Brown deposit in a field?" , "Particular cock" , "Piece of cattle dung" .)

I've seen this clue in The Telegraph.

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