___ mattress (3)
'mattress' is the definition.
This is all the clue.
(Other definitions for bed that I've seen before include "Bottom < layer" , "Bottom of the sea or river" , "In which to place the body of flowers" , "Couch" , "For sleep and flowers" .)
'mattress' is the definition.
(air mattress is a kind of mattress)
This is the entire clue.
(Other definitions for air that I've seen before include "Simple melody's" , "put on radio?" , "Cause of inflation" , "Space above and around" , "Simple tune" .)