The most common and most likely answer to this crossword clue is the 9 letter word ADAPTOGEN
I've seen this crossword clue in Financial Times
A
D
A
P
T
O
G
E
N
Buddy explains!
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 ADAPTOGEN mean?
ADAPTOGEN noun- Any natural herbal substance (such as ginseng) that is supposed to help the body adapt to stress, and to exert a normalizing effect upon body functions.