Do thermostats control it? (12)

I believe the answer is:

housewarming

I'm a little stuck... Click here to teach me more about this clue!

'do' is the definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.

I don't understand the remainder of the clue.

Can you help me to learn more?

I've seen this clue in The Independent.

Want a hint initially instead of a full solution? Install my app