A hovel, including very last shelter (6)
I believe the answer is:
asylum
'shelter' is the definition.
(asylum is a kind of shelter)
'a hovel including very last' is the wordplay.
'hovel' becomes 'slum'.
'including' indicates putting letters inside.
'last' indicates one should take the final letters.
The last letter of 'very' is 'y'.
'slum' placed around 'y' is 'sylum'.
'a'+'sylum'='ASYLUM'
(Other definitions for asylum that I've seen before include "Institution for care of the insane" , "'Refuge, sanctuary (6)'" , "Refuge or home for mentally ill" , "Haven or hospital for the mentally ill" , "Place of refuge, once a mental institution" .)