Instrument this French alto carries in case (7)
I believe the answer is:
celesta
'instrument' is the definition.
(celesta is a kind of instrument)
'this french alto carries in case' is the wordplay.
'this french' becomes 'ce' (I've seen this in other clues).
'alto' becomes 'a' (this could be a standard abbreviation of which I'm unaware).
'carries' says to put letters next to each other (in a down clue, some letters go beneath others).
'in case' becomes 'lest' (I've seen this before).
'a' put after 'lest' is 'lesta'.
'ce'+'lesta'='CELESTA'
Can you help me to learn more?
(Other definitions for celesta that I've seen before include "Play this" , "a bunch of keys?" , "one giving out notes" , "Keyboard percussion instrument giving a bell-like sound" , "Musical instrument" .)