Bury Orion on going inside (8)
I believe the answer is:
interior
'inside' is the definition.
(similar in meaning)
'bury orion on going' is the wordplay.
'bury' becomes 'inter' (to inter is to put into the ground).
'orion on going' becomes 'ior' (I can't justify this - if you can you should believe this answer much more).
'inter'+'ior'='INTERIOR'
Can you help me to learn more?
(Other definitions for interior that I've seen before include "Private" , "Situated inside" , "Inside part" , "The area inside" , "The heart" .)