Maybe sweaty husband enters having too much on his plate? (11)

I believe the answer is:

overheating

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'maybe sweaty husband enters having too much on his plate?' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how they can define each other.

'on his plate?' is the wordplay.
'on' becomes 'over' (over can mean on top of).
'his plate?' becomes 'heating' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'over'+'heating'='OVERHEATING'

Can you help me to learn more?

I've seen this clue in The Times.

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