All but the two of us will reject hot drink (4-4)
I believe the answer is:
well-nigh
'all but the two' is the definition.
I can't judge whether this defines the answer.
'us will reject hot drink' is the wordplay.
'us' becomes 'we'.
'will' becomes ''ll'.
'reject' shows that the letters should be reversed in order.
'hot' becomes 'h' (abbreviation eg on taps).
'drink' becomes 'gin' (gin is a kind of drink).
'h'+'gin'='hgin'
'hgin' back-to-front is 'nigh'.
'we'+'ll'+'nigh'='WELL-NIGH'
'of' acts as a link.
Can you help me to learn more?
(Other definitions for well-nigh that I've seen before include "Healthy plus near = almost" , "Amost, very nearly" .)