Nominally, being French, I take a year (4)
I believe the answer is:
'a year' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'nominally being french i' is the wordplay.
I cannot really see how this works, but
'i' could be 'a' and 'a' is present in the answer.
The remaining letters 'jen' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'take' is the link.
Can you help me to learn more?
(Other definitions for jean that I've seen before include "Material" , "Frenchman" , "Englishwoman having pronounced difference" , "Heavy cloth, denim" , "English girl - French boy" .)