False move up in public transport (5)
I believe the answer is:
bogus
'false' is the definition.
(I've seen this in another clue)
'move up in public transport' is the wordplay.
'move' becomes 'go' (to go is to move).
'up' says the letters should be written in reverse (in down clue: letters go upwards).
'in' means one lot of letters goes inside another.
'public transport' becomes 'bus' (bus is a kind of public transport).
'go' written backwards gives 'og'.
'og' placed within 'bus' is 'BOGUS'.
(Other definitions for bogus that I've seen before include "Scribbled drawing" , "Fake, sham" , "false impression" , "Not genuine, sham" , "Pretended" .)