See a hundred relations making time for private drink (4-2)
I believe the answer is:
lock-in
'time for private drink' is the definition.
I can't judge whether this definition defines the answer.
'see a hundred relations' is the wordplay.
'see' becomes 'lo' ('lo' is an archaic exclamation meaning 'look!').
'a hundred' becomes 'C' (Roman numerals).
'relations' becomes 'kin' (I've seen this in other clues).
'lo'+'c'+'kin'='LOCK-IN'
'making' acts as a link.
Can you help me to learn more?
(Another definition for lock-in that I've seen is " Illegal extension of pub drinking time".)