French girl returns if encored (4)

I believe the answer is:

fifi

I'm a little stuck... Click here to teach me more about this clue!

'encored' is the definition.
I don't know anything about this answer so I cannot tell whether it can be defined by this definition.

'french girl returns if' is the wordplay.
'french girl' becomes 'fi' (nickname for Fiona. I am not sure about the 'french' bit.).
'returns' shows that the letters should be reversed in order.
'if' back-to-front is 'fi'.
'fi'+'fi'='FIFI'

Can you help me to learn more?

I've seen this clue in The Globe and Mail.

Want a hint initially instead of a full solution? Install my app