Soften edge of snooker table (7)

I believe the answer is:

cushion

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'soften' is the definition.
(I know that soften can be written as cushion)

I don't understand the rest of the clue.

(Other definitions for cushion that I've seen before include "Protect from blow" , "Dampen" , "Large pad" , "Part of a billiard table" , "See 9" .)

I've seen this clue in The Sun.

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