One spent in Lincoln, possibly? (4)
I believe the answer is:
coin
'one' is the definition.
Although both the answer and definition are singular nouns, I don't understand how one could define the other.
'spent in lincoln possibly?' is the wordplay.
I cannot really see how this works, but
'in' is within the answer.
The remaining letters 'co' 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 coin that I've seen before include "Think up" , "Make up" , "little money" , "Mint" , "Create (phrase); metal token" .)