One point against OAPs? (5)

I believe the answer is:

agist

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'oaps?' is the definition.
I can't tell whether this defines the answer.

'one point against' is the wordplay.
'one' becomes 'a' (a thing is one thing).
'point' becomes 'gist' (I've seen this before).
'against' says to put letters next to each other.
'a'+'gist'='AGIST'

Can you help me to learn more?

(Other definitions for agist that I've seen before include "Prejudiced against older persons" , "Not liking the elderly" , "less pleasant to older folks, perhaps" , "Take in and feed" .)

I've seen this clue in The Independent.

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