Hip play in French theatre's opening — each across solution has one (10)
I believe the answer is:
instrument
'opening each across solution has one' is the definition.
I can't tell whether this definition defines the answer.
'hip play in french theatre's' is the wordplay.
'hip' becomes 'in' (both can mean fashionable).
'play' becomes 'strum' (I've seen this before).
'in french' becomes 'en' ('in' in French).
'theatre's' becomes 't' (this could be a standard abbreviation which I don't know about).
'in'+'strum'+'en'+'t'='INSTRUMENT'
Can you help me to learn more?
(Other definitions for instrument that I've seen before include "power" , "legal document" , "Joanna, perhaps" , "What's needed for 1 [MUSICIAN]" , "Means of precision work (or music-making)" .)