Falls about and cheers Queen show (8)
I believe the answer is:
cataract
'falls' is the definition.
(synonyms)
'about and cheers queen show' is the wordplay.
I cannot really see how this works, but
'about' could be 'ca' (short for circa) and 'ca' is present in the answer.
'cheers' could be 'ta' (both can informally mean thank you) and 'ta' is located in the answer.
'queen' could be 'r' (abbreviation for regina, e.g. in ER ) and 'r' is present in the answer.
'show' could be 'act' (act is a kind of show) and 'act' is found within the answer.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for cataract that I've seen before include "Fall of water or eye ailment" , "Falls" , "Waterfall and eye defect" , "It may prevent someone seeing" , "Waterfall - eye problem" .)