The most common and most likely answer to this crossword clue is the 11 letter word DISAFFECTED
I've seen this crossword clue in The Times
D
I
S
A
F
F
E
C
T
E
D
Buddy explains!
The straight part
We know that "Alienated" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case alienated = disaffected.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 DISAFFECTED mean?
DISAFFECTED verb- To cause a loss of affection, sympathy or loyalty in; to alienate or estrange.
- Alienated or estranged, often with hostile effect; rebellious, resentful; disloyal.
- Affected with disease.