Indicates one's had enough, in exasperation, and points to instrument case? (5,2)
I believe the answer is:
thats it
'indicates one's had enough in exasperation' is the definition.
I know nothing about this answer so I cannot tell whether this works.
'points to instrument case?' is the wordplay.
'points to' becomes 'thats' (I can't justify this - if you can you should believe this answer much more).
'case?' says to hollow out the word (remove centre letters) (I've seen 'cases of' mean this).
'instrument' with its centre taken out is 'it'.
'thats'+'it'='THATS IT'
'and' acts as a link.
Can you help me to learn more?
(Another definition for thats it that I've seen is " There's no more".)