Person holding cup? I bet that gets smashed — it’s what impatient waiters do (5,2,3,3)
I believe the answer is:
champ at the bit
'person holding cup?' is the definition.
I know nothing about this answer so I can't judge whether this works.
'i bet that gets smashed it's what impatient waiters do' is the wordplay.
I cannot really understand how this works, but
'i' could be 'a' and 'a' is located in the answer.
an anagram of 'that' is 'atth' which is located in the answer.
'it' could be 't' (abbreviation. e.g. in 'tis) and 't' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for champ at the bit that I've seen before include "Show impatience to begin" , "Be impatient to start" , "Be eager to begin" , "can't wait!" , "Be eager to start" .)