Comeback married couple welcome (7)
I believe the answer is:
embrace
'welcome' is the definition.
(I've seen this before)
'comeback married couple' is the wordplay.
'comeback' becomes 'em' (I can't justify this - if you can you should believe this answer much more).
'married' means one lot of letters go next to another.
'couple' becomes 'brace' (brace can mean a pair of something).
'em'+'brace'='EMBRACE'
Can you help me to learn more?
(Other definitions for embrace that I've seen before include "bear-hug?" , "Hold closely, include" , "Hug; adopt" , "Warmly welcome" , "Include (in one's arms)" .)