Wash Fido and he can sit on you madam (6)

I believe the answer is:

lapdog

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'wash fido and he can sit on you madam' is the definition.
Although both the answer and definition are singular nouns, I don't see how one could define the other.

This is the entire clue.

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(Other definitions for lapdog that I've seen before include "one of man's more diminutive best friends" , "Small pampered pet" , "Small pampered pooch" , "Small pet - sycophant" , "One readily submitting" .)

I've seen this clue in the Evening Standard.

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