Way out of planet (4)
I believe the answer is:
lane
'way' is the definition.
(I know that lane is a type of way)
'of planet' is the wordplay.
'of' says the answer is hidden in the clue.
'LANE' is hidden within 'planet'.
'out' is the link.
(Other definitions for lane that I've seen before include "Narrow rural road" , "Byroad" , "Footpath" , "Quiet road" , "Passage" .)