Dizzy feeling (7)
I believe the answer is:
vertigo
'dizzy feeling' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for vertigo that I've seen before include "Dizzy sensation brought on by heights" , "Disturbance in the inner ear" , "Type of dizziness associated with fear of heights" , "Forty Thieves' password" , "Sense of dizziness - Hitchcock film" .)