The most common and most likely answer to this crossword clue is the 9 letter word SOLIPSISM
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More clues leading to the result SOLIPSISM
Buddy explains!
The straight part
We know that "egocentric behaviour" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case egocentric behaviour = solipsism.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 SOLIPSISM mean?
SOLIPSISM noun- The theory that the self is all that exists or that can be proven to exist.
- Self-absorption, an unawareness of the views or needs of others; self-centeredness; egoism.