Curious disposition around City is on the level? (9)

I believe the answer is:

recumbent

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'on the level?' is the definition.
I can't judge whether this defines the answer.

'curious disposition around city' is the wordplay.
'curious' becomes 'rum' (synonyms).
'disposition' becomes 'bent' (bent is a kind of disposition).
'around' means one lot of letters goes inside another.
'city' becomes 'EC' (the City of London postcode).
'rum'+'bent'='rumbent'
'rumbent' enclosing 'ec' is 'RECUMBENT'.

'is' acts as a link.

Can you help me to learn more?

(Other definitions for recumbent that I've seen before include "flat?" , "Lying down comfortably" .)

I've seen this clue in The Times.

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