Is fast finding what all the study was for (7)
I believe the answer is:
careers
'is' is the definition.
Although both the answer and definition are verbs in their -s form, I don't understand how one could define the other.
'fast finding what all the study was for' is the wordplay.
I cannot quite understand how this works, but
'study' could be 'ee' (EE is an example) and 'ee' is found in the answer.
The remaining letters 'carrs' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for careers that I've seen before include "Vocations" , "Moves at reckless speed" , "jobs" , "Rushes" .)