Agreements of EU board (5)

I believe the answer is:

ouija

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'board' is the definition.
(I know that Ouija is a type of board)

I can't explain the remainder of the clue.

(Other definitions for ouija that I've seen before include "Board for contacting spirits" , "This board is used in spiritualist proceedings" , "This board is used in spiritualistic sessions" , "(Seance) lettered board" , "Board used in spiritualist session" .)

I've seen this clue in The Guardian.

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