Friend that is holding down fence (8)

I believe the answer is:

palisade

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'fence' is the definition.
('palisade' can be a synonym of 'fence')

'friend that is holding down' is the wordplay.
'friend' becomes 'pal' (pal is a kind of friend).
'that is' becomes 'is'.
'holding down' becomes 'ade' (I can't justify this - if you can you should believe this answer much more).
'pal'+'is'+'ade'='PALISADE'

Can you help me to learn more?

(Other definitions for palisade that I've seen before include "paling" , "defence work" , "Fence of stakes or iron railings" , "Fence consisting of stakes" , "Line of stakes as a defence" .)

I've seen this clue in The Telegraph.

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