The most common and most likely answer to this crossword clue is the 7 letter word TOPCOAT
I've seen this crossword clue in The Sunday Telegraph
T
O
P
C
O
A
T
More clues leading to the result TOPCOAT
- Cartoon gang leader retains old clothing
- Perfectly concealing cop-out in Ulster?
- Perhaps Ulster‘s best film
- Garment that’s the last thing painter puts on
- The best company at producing cold weather gear
- Ulster’s best firm volunteers returns
- Piece of attire for primarily tough work on shore, not small
- Warm garment that could be glossy
Buddy explains!

The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does TOPCOAT mean?
TOPCOAT noun- A light overcoat.
- A layer of paint or varnish etc. applied after the undercoat.
- To apply a topcoat to.