Charter from Queen in rush (4)
I believe the answer is:
hire
'charter' is the definition.
(synonyms)
'queen in rush' is the wordplay.
'queen' becomes 'r' (r is abbreviation regina. e.g. in ER ).
'in' is an insertion indicator.
'rush' becomes 'hie' (synonyms).
'r' put within 'hie' is 'HIRE'.
'from' acts as a link.
(Other definitions for hire that I've seen before include "Rent, employ" , "Engage (taxi)" , "Rent or lease" , "Pay to use something" , "Charter, employ" .)