The most common and most likely answer to this crossword clue is the 7 letter word STRAYED
I've seen this crossword clue in Independent
S
T
R
A
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D
Buddy explains!
The straight part
We know that "Fell from grace/lacked herd mentality?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fell from grace/lacked herd mentality? = strayed.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 STRAYED mean?
STRAYED verb- To wander, as from a direct course; to deviate, or go out of the way.
- To wander from one's limits; to rove or roam at large; to go astray.
- To wander from the path of duty or rectitude; to err.
- To cause to stray.
- Having lost one's way; wandering; astray.