The most common and most likely answer to this crossword clue is the 8 letter word PLAINEST
I've seen this crossword clue in The Daily Telegraph
P
L
A
I
N
E
S
T
More clues leading to the result PLAINEST
Buddy explains!
The straight part
We know that "Most unattractive" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case most unattractive = plainest.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 PLAINEST mean?
PLAINEST adjective- Flat, level.
- Simple.
- Obvious.
- Open.
- Not unusually beautiful; unattractive.
- Not a trump.