Frenzied French worker perhaps in charge (7)
I believe the answer is:
frantic
'frenzied' is the definition.
(I know that frenzied can be written as frantic)
'french worker perhaps in charge' is the wordplay.
'french' becomes 'fr' (abbreviation).
'worker perhaps' becomes 'ant' (worker is a type of ant).
'in charge' becomes 'ic' (abbreviation for 'in charge').
'fr'+'ant'+'ic'='FRANTIC'
(Other definitions for frantic that I've seen before include "Distracted" , "having kittens" , "Desperate with worry" , "Beside oneself" , "Overwrought" .)