Patent feature of a hover train (5)
I believe the answer is:
overt
'patent' is the definition.
(both can mean obvious)
'feature of a hover train' is the wordplay.
'feature of' indicates the answer is hidden within the clue.
'OVERT' is hidden in the letters of 'hover train'.
(Other definitions for overt that I've seen before include "Open, up front" , "Obvious, patent" , "Open, not secret or hidden" , "Open, not 1 across" , "Voter (anag.)" .)