Showy Georgia and upper-class detective start to yawn (5)
I believe the answer is:
gaudy
'showy' is the definition.
(I know that showy can be written as gaudy)
'georgia and upper-class detective start to yawn' is the wordplay.
'georgia' becomes 'GA' (abbreviation).
'and' means one lot of letters go next to another.
'upper-class detective' becomes 'ud' (this could be a standard abbreviation I've not previously seen).
'start to' suggests taking the first letters.
The first letter of 'yawn' is 'y'.
'ga'+'ud'+'y'='GAUDY'
Can you help me to learn more?
(Other definitions for gaudy that I've seen before include "Tastelessly bright" , "celebrations in college" , "celebration in college" , "Vulgarly bright" , "College feast" .)