The Roman I have in mind (3)
I believe the answer is:
ego
This could be a double definition.
'the roman i' is the first definition.
(I've seen this in another clue)
'in mind' is the second definition.
'ego' can be an answer for 'mind' (I have seen 'Conscious mind ' mean 'ego' so perhaps 'mind' could also mean 'ego'). I am not certain of the 'in' bit.
'have' is the link.
Can you help me to learn more?
(Other definitions for ego that I've seen before include "Self-esteem or self-importance" , "Sense of self, conceit" , "Conscious self" , "Self-esteem, conceit" , "Selfishness" .)