Lift to reveal switch (8)
I believe the answer is:
elevator
'lift' is the definition.
(I know that lift can be written as elevator)
'to reveal switch' is the wordplay.
'switch' is an anagram indicator.
'to'+'reveal'='toreveal'
'toreveal' with letters rearranged gives 'ELEVATOR'.
(Other definitions for elevator that I've seen before include "US lift" , "may give you a lift" , "North American lift" , "one that goes up and down" , "A lift in America" .)