Snaps baker's crackers (6)
I believe the answer is:
breaks
'snaps' is the definition.
(I've seen this before)
'baker's crackers' is the wordplay.
'crackers' indicates an anagram (informal term for mad).
'bakers' with letters rearranged gives 'BREAKS'.
(Other definitions for breaks that I've seen before include "Interruptions of continuity" , "Fractures or splits" , "Snaps; holidays" , "Intervals" , "Ruptures" .)