Advance plane underwater (10)

I believe the answer is:

subsurface

'underwater' is the definition.
(similar in meaning)

'advance plane' is the wordplay.
'advance' becomes 'sub' (both can mean a loan).
'plane' becomes 'surface' (plane can mean a flat surface).
'sub'+'surface'='SUBSURFACE'

I've seen this clue in The Daily Express.

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