Open to accusation of looking stupid? (5)

I believe the answer is:

agape

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'open' is the definition.
('agape' can be similar in meaning to 'open')

I cannot understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for agape that I've seen before include "the love of God!" , "love feast" , "love a Christian shows" , "(Of mouth) wide open" , "Astonished" .)

I've seen this clue in the Evening Standard.

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