Journey uncovered groups of lions (4)
I believe the answer is:
ride
'journey' is the definition.
(riding is a kind of journeying)
'uncovered groups of lions' is the wordplay.
'uncovered' indicates the central letters.
'groups of lions' becomes 'prides' (I've seen this in another clue).
The central letters of 'prides' are 'RIDE'.
(Other definitions for ride that I've seen before include "Eg, roundabout or roller-coaster, path for horses" , "Travel (on a bike, perhaps)" , "Travel on (a bicycle)" , "Fairground entertainment" , "A dire sort of journey" .)