Getting down? Not getting down (13)

I believe the answer is:

understanding

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'getting' is the definition.
(get can mean to understand or appreciate)

'down? not getting down' is the wordplay.
'down?' becomes 'under' (under means further down).
'not getting down' becomes 'standing' (I can't explain this - if you can you should believe this answer much more).
'under'+'standing'='UNDERSTANDING'

Can you help me to learn more?

(Other definitions for understanding that I've seen before include "Knowledge" , "Compassion" , "Empathy" , "compassionate" , "Discernment" .)

I've seen this clue in The Times.

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