Eagerly take in being a whole circuit ahead (3,2)

I believe the answer is:

lap up

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'eagerly take in being a whole' is the definition.
I can't tell whether this defines the answer.

'circuit ahead' is the wordplay.
'circuit' becomes 'lap' (synonyms).
'ahead' becomes 'up' (similar in meaning).
'lap'+'up'='LAP UP'

Can you help me to learn more?

(Other definitions for lap up that I've seen before include "Drink (water) like a dog" , "Accept eagerly" , "Relish (with the tongue?)" , "Scoop" , "of future monarch?" .)

I've seen this clue in The Times.

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