Giddy (5)
I believe the answer is:
dizzy
'giddy' is the definition.
(I know that giddy can be written as dizzy)
This is the entire clue.
(Other definitions for dizzy that I've seen before include "Giddy, confused" , "Giddy - silly" , "Giddy - flighty" , "Light-headed -- bewildered" , "- Gillespie, trumpeter" .)