The most common and most likely answer to this crossword clue is the 12 letter word PSYCHOLOGIES
I've seen this crossword clue in The Daily Telegraph
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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 PSYCHOLOGIES mean?
PSYCHOLOGIES noun- The study of the human mind.
- The study of human behavior.
- The study of animal behavior.
- The mental, emotional, and behavioral characteristics pertaining to a specified person, group, or activity.