Crossword Genius

Infidelity of professor after drinking a bit of rum at the end of party (9)

Ross

I believe the answer is:

treachery

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(Other definitions for treachery that I've seen before include "Perfidious behaviour" , "Perfidy" , "lack of loyalty" , "Two-timing" , "Double-dealing" .)

I've seen this clue in The Hindu.
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