It may come down and go up (4)

I believe the answer is:

bomb

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'it may come down and go up' is the definition.
The definition suggests a singular noun which matches the answer.

This is the entire clue.

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(Other definitions for bomb that I've seen before include "Incendiary device" , "lot of money" , "Load of money (slang)" , "Big bucks - flop" , "See 18" .)

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