The most common and most likely answer to this crossword clue is the 9 letter word ABERRANCE
A
B
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R
R
A
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E
More clues leading to the result ABERRANCE
- Overcoming resistance, president conducted cosmic expedition’s starting points and departure
- Lincoln rector originally managed church going in the wrong direction
- Deviation from normal unusually rare? Can be
- Abnormality is a beer can mistakenly having a little rum
- Overcoming resistance, president conducted cosmic expedition's starting points and departure
- Yogi's enthralled by boundless flings and deviant behavior
Buddy explains!

The straight part
We know that "departure" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case departure = aberrance.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.