Girl's coin the same however you flip it (4)

I believe the answer is:

anna

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'girl's coin' is the definition.
'anna' can be an answer for 'coin' (I have seen 'Old coin' mean 'anna' so perhaps 'coin' could also mean 'anna'). I am not certain of the 'girl's' bit.

I can't explain the rest of the clue.

Can you help me to learn more?

(Other definitions for anna that I've seen before include "She's a woman, whichever way you look at it" , "Old foreign coin" , "- - Kournikova (tennis)" , "- - Ford (TV)" , "Massey, Sewell or Karenina" .)

I've seen this clue in The Independent.

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