The most common and most likely answer to this crossword clue is the 6 plus 4 letter word DOUBLE CHIN
I've seen this crossword clue in The Guardian
D
O
U
B
L
E
C
H
I
N
More clues leading to the result DOUBLE CHIN
- Feature of fat person suggesting good health?
- Could be unfit: primarily heavy with it?
- Those partial to chicken and chips in for unsightly fat!
- Hitchcock’s outstanding feature?
- Facial feature two inches out?
- Good health on the face of it!
- Not a single feature that would make old-style toast
- Extra fat in good health?
- Unattractive feature in toast?
Buddy explains!
The straight part
We know that "Not a single feature" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case not a single feature = double chin.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.