Hats and clothes for a principal? (8)
I believe the answer is:
headgear
'hats' is the definition.
(I've seen this before)
'clothes for a principal?' is the wordplay.
'clothes' becomes 'gear' (I've seen this before).
'for' means one lot of letters go next to another (I've seen this in other clues).
'a principal?' becomes 'head' ('head' can be a synonym of 'principal').
'gear' after 'head' is 'HEADGEAR'.
'and' is the link.
(Other definitions for headgear that I've seen before include "Mortarboard < , especially" , "Balmoral, perhaps" , "crown, say" , "helmet, for instance" , "Perhaps a hat" .)