Maybe pass a number in a sudden burst! (5)
I believe the answer is:
spasm
'a sudden burst' is the definition.
(I've seen this in another clue)
'maybe pass a number' is the wordplay.
'maybe' is an anagram indicator.
'a number' becomes 'm' (M is an example).
'pass' anagrammed gives 'spas'.
'spas'+'m'='SPASM'
'in' acts as a link.
(Other definitions for spasm that I've seen before include "Involuntary muscular movement" , "Jerk" , "Fit" , "Convulsive action" , "Convulsion or paroxysm" .)