Catch in lone trap (3)
I believe the answer is:
net
'catch' is the definition.
(I know that net is a type of catch)
'in lone trap' is the wordplay.
'in' says the answer is hidden in the clue.
'NET' can be found hidden inside 'lone trap'.
(Other definitions for net that I've seen before include "Fish-catching mesh" , "It turns in every direction" , "Fish-catcher" , "It's see-through" , "Catch, ensnare" .)