The most common and most likely answer to this crossword clue is the 12 letter word HYPNOTHERAPY
H
Y
P
N
O
T
H
E
R
A
P
Y
More clues leading to the result HYPNOTHERAPY
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 HYPNOTHERAPY mean?
HYPNOTHERAPY noun- Treatment of disease by means of hypnotism.