Deep down in part of hospital, emptied lorry (8)
I believe the answer is:
inwardly
'deep down' is the definition.
(both can mean internally or subconsciously)
'in part of hospital emptied lorry' is the wordplay.
'part of hospital' becomes 'ward' ('ward' is part of 'hospital').
'emptied' means to remove the middle letters.
'lorry' with its middle taken out is 'ly'.
'in'+'ward'+'ly'='INWARDLY'
(Other definitions for inwardly that I've seen before include "to the centre" , "Mentally or spiritually" , "In the heart, privately" , "secretly" .)