Mother, terribly energetic, using heat (13)

I believe the answer is:

thermodynamic

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'heat' is the definition.
The answer and definition are not the same part of speech.

'mother terribly energetic' is the wordplay.
'terribly' indicates an anagram.
'energetic' becomes 'dynamic' (associated in meaning).
'mother' anagrammed gives 'thermo'.
'thermo'+'dynamic'='THERMODYNAMIC'

'using' acts as a link.

Can you help me to learn more?

(Other definitions for thermodynamic that I've seen before include "Relating heat to energy" , "Temperature expressed on the Kelvin scale" .)

I've seen this clue in The Daily Express.

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