Cool couple needs some in 2 to dress down (2,7)
I believe the answer is:
in despair
'2 to dress down' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.
'cool couple needs some in' is the wordplay.
'cool' becomes 'in' ('in' can mean fashionable or cool).
'couple' becomes 'pair' (synonyms).
'needs some' becomes 'des' (I can't explain this - if you can you should believe this answer much more).
'in' indicates putting letters inside.
'in'+'pair'='inpair'
'inpair' going around 'des' is 'IN DESPAIR'.
Can you help me to learn more?
(Other definitions for in despair that I've seen before include "Affected by a feeling of hopelessness" , "at wits' end" .)