Gay miss who waves about? (7)
I believe the answer is:
flapper
'gay miss' is the definition.
'flapper' can be an answer for 'miss' (flapper is a kind of miss). I am not sure about the 'gay' bit.
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for flapper that I've seen before include "Fashionable young woman of the 1920s" , "one inclined to panic" , "Unconventional young woman in the 1920s" , "girl in 20s" , "fashionable female in twenties" .)