Driver wildly interrupting acclamation (10)
I believe the answer is:
charioteer
'driver' is the definition.
(charioteer is a kind of driver)
'wildly interrupting acclamation' is the wordplay.
'wildly' becomes 'ariot' (old-fashioned adverb).
'interrupting' indicates putting letters inside.
'acclamation' becomes 'cheer'.
'ariot' going into 'cheer' is 'CHARIOTEER'.
(Other definitions for charioteer that I've seen before include "chap driving old vehicle" , "Driver of horse-drawn fighting vehicle" , "Porphyrius perhaps" , "Hippodrome racer" , "Driver of Roman vehicle" .)