Job prolonged invasion (10)
I believe the answer is:
occupation
This could be a double definition.
'job' is the first definition.
(I know that job can be written as occupation)
'prolonged invasion' is the second definition.
The answer and definition can be both acts as well as being singular nouns.
Maybe you can see an association between them that I can't see?
Can you help me to learn more?
(Other definitions for occupation that I've seen before include "Calling" , "period of residency" , "Business - residence" , "end of invasion?" , "Job, profession" .)