Perhaps, extremely bossy person at No 11 firing 14 after review (2,6)
I believe the answer is:
by chance
'perhaps' is the definition.
'extremely bossy person at no 11 firing 14 after review' is the wordplay.
I cannot quite see how this works, but
'no' could be 'n' (common abbreviation) and 'n' is found in the answer.
'person' could be 'ace' (ace is a kind of person) and 'ace' is found within the remaining letters.
This may be the basis of clue (or it may be nonsense).
(Other definitions for by chance that I've seen before include "Fortuitously" , "Unplanned, as it happened" , "As it happened, without being planned" , "Without advance planning" , "Accidentally, not planned" .)