Engrossed in getting into gear? (7)
I believe the answer is:
engaged
'engrossed in' is the definition.
(thesaurus)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for engaged that I've seen before include "Promised in marriage" , "Busy - fiancee" , "Held" , "Formally committed to marriage" , "Plighted; hired" .)