Out when shelter promised initially (6)
I believe the answer is:
asleep
'out' is the definition.
(thesaurus)
'when shelter promised initially' is the wordplay.
'when' becomes 'as'.
'shelter' becomes 'lee' (I've seen this before).
'initially' says to take the initial letters.
The first letter of 'promised' is 'p'.
'as'+'lee'+'p'='ASLEEP'
(Other definitions for asleep that I've seen before include "Napping" , "Dormant; inattentive" , "Please be at rest (6)." , "in bed?" , "Please (anag) - numb" .)