For a start, is it socially acceptable to be in debt? (5)
I believe the answer is:
debut
'for a start' is the definition.
(debut is a kind of start)
'acceptable to be in debt?' is the wordplay.
'acceptable' becomes 'u' (as in U and non-U speech).
'to be in' means one lot of letters goes inside another.
'u' placed inside 'debt' is 'DEBUT'.
'is it socially' is the link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for debut that I've seen before include "First appearance, a coming-out" , "opening" , "Tubed (anag.)" , "where one began" , "Aurora" .)