Rush as hen sat around (6)
I believe the answer is:
hasten
'rush' is the definition.
(I know that rush can be written as hasten)
'hen sat around' is the wordplay.
'around' indicates anagramming the letters.
'hen'+'sat'='hensat'
'hensat' with letters rearranged gives 'HASTEN'.
'as' acts as a link.
(Other definitions for hasten that I've seen before include "Speed up" , "race? - with 26a" , "Be quick to do something" , "Step up" , "Make faster" .)