The most common and most likely answer to this crossword clue is the 8 letter word OUTSIDER
I've seen this crossword clue in The Daily Telegraph
O
U
T
S
I
D
E
R
More clues leading to the result OUTSIDER
- Blooming drink that's said to be no favourite
- Not a favourite Camus character?
- Studio broadcast about backing long shot
- Unfashionable drink, we hear, non-member required
- 1000/1 shot‘s detour is funny
- Not one of the favourites is rude to eccentric
- Not one of us will change our diets
- Doctor is rude to stranger
- Awfully tedious Republican who’s unlikely to win?
- Foreign party unconscious on drink, we hear
Buddy explains!

The straight part
We know that "stranger" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case stranger = outsider.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 OUTSIDER mean?
OUTSIDER noun- One who is not part of a community or organization.
- A newcomer with little or no experience in an organization or community.
- A competitor or contestant who has little chance of winning; a long shot