Girl loses her head over slang (5)
I believe the answer is:
argot
'slang' is the definition.
(synonyms)
'girl loses her head over' is the wordplay.
I cannot really understand how this works, but
'girl' could be 'g' and 'g' is present in the answer.
'over' could be 'o' (cricket abbreviation) and 'o' is present in the answer.
The remaining letters 'art' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for argot that I've seen before include "manner of speaking" , "Special language of a groat?" , "secret language" , "Special jargon of a group" , "Jargon - patois" .)