Gaudy (6)
I believe the answer is:
garish
'gaudy' is the definition.
(I know that gaudy can be written as garish)
This is all the clue.
(Other definitions for garish that I've seen before include "Crudely bright" , "Cheap, flash" , "Cheap, flashy" , "in bright colours" , "Gaudy, lurid" .)