Bone in heap, not quite dead? (8)
I believe the answer is:
moribund
'not quite dead?' is the definition.
(I've seen this before)
'bone in heap' is the wordplay.
'bone' becomes 'rib' (rib is a kind of bone).
'in' means one lot of letters goes inside another.
'heap' becomes 'mound' (synonyms).
'rib' inserted inside 'mound' is 'MORIBUND'.
(Other definitions for moribund that I've seen before include "About to die" , "not quite dead" , "Near to death" , "lacking vitality" , "In a dying state" .)