I have nothing on for example... (3)
I believe the answer is:
ego
'i' is the definition.
('I' in Latin)
'nothing on for example' is the wordplay.
'nothing' becomes 'O' (looks like zero - 0).
'on' says to put letters next to each other.
'for example' becomes 'e.g.' (short for 'exempli gratia', 'for example' in Latin).
'o' after 'eg' is 'EGO'.
'have' is the link.
(Other definitions for ego that I've seen before include "Personal pride" , "Conscious mind" , "Sense of identity" , "Vowel to disappear, < say another" , "Inner self" .)