… that's out dreaming? (6)
I believe the answer is:
asleep
I believe this is a double definition.
'that's out' is the first definition.
(out can mean unconscious or asleep)
'dreaming?' is the second definition.
(I've seen this in another clue)
(Other definitions for asleep that I've seen before include "Slumbering" , "in bed?" , "Out for the count" , "Dormant, inactive" , "Please be at rest, oddly" .)