Separate underwater swimmer, say, surfacing (7)

I believe the answer is:

diverge

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'separate' is the definition.
(I've seen this before)

'underwater swimmer say surfacing' is the wordplay.
'underwater swimmer' becomes 'diver' (diver is a kind of swimmer. I am not sure about the 'underwater' bit.).
'say' becomes 'eg' (both can mean 'for example').
'surfacing' is a reversal indicator (as opposed to capsizing).
'eg' written backwards gives 'ge'.
'diver'+'ge'='DIVERGE'

Can you help me to learn more?

(Other definitions for diverge that I've seen before include "Bifurcate" , "Drift apart" , "Go different ways" , "Branch off" , "Move away from" .)

I've seen this clue in The Telegraph.

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