The earth? Throw into empty grave (5)
I believe the answer is:
globe
'the earth?' is the definition.
('globe' can be a synonym of 'earth')
'throw into empty grave' is the wordplay.
'throw' becomes 'lob' (to lob something is to chuck or throw it).
'into' is an insertion indicator.
'empty' means to remove the middle letters.
'grave' with its middle removed is 'ge'.
'lob' placed into 'ge' is 'GLOBE'.
(Other definitions for globe that I've seen before include "Boston, MA's newspaper" , "House 8 [OF SHAKESPEARE]" , "Spherical shape" , "The round world" , "Earth - sphere" .)