This in small chamber orchestra for a start? (5)
I believe the answer is:
cello
'this in small chamber orchestra for a start?' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'this in small chamber' is the wordplay.
I cannot really see how this works, but
'chamber' could be 'cell' (I've seen this before) and 'cell' is found in the answer.
A single letter 'o' remains which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for cello that I've seen before include "Music-maker" , "music produced by this?" , "Tortelier's instrument" , "Played by Rostropovich" , "Musical instrument like large violin held between legs" .)