More income by and by (8)
I believe the answer is:
overtime
'by' is the definition.
Both the answer and definition are adverbs. Maybe they are linked in a way I don't understand?
'more income by' is the wordplay.
'more' becomes 'over' (I've seen this before).
'income' becomes 'time' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'by' means one lot of letters go next to another.
'over'+'time'='OVERTIME'
'and' is the link.
Can you help me to learn more?
(Other definitions for overtime that I've seen before include "Work outside normal hours" , "Pay for extra work" , "Work in excess of fixed period" , "Hours worked in excess of usual" , "Work beyond normal hours? Remove it" .)