Cast iron contains note for use within the home (6)
I believe the answer is:
indoor
'for use within the home' is the definition.
(for indoor use)
'cast iron contains note' is the wordplay.
'cast' indicates anagramming the letters (letters are dispersed or cast around).
'contains' indicates putting letters inside.
'note' becomes 'do' (musical note, as in do-re-mi).
'iron' is an anagram of 'inor'.
'inor' placed around 'do' is 'INDOOR'.
(Other definitions for indoor that I've seen before include "These sports are roofed" , "Not outside the home" , "Situated within a building - maybe a sport" , "away from the other elements" , "not alfresco" .)