Mean, despicable, or morally low behavior; actions that are cowardly, underhanded, or contemptible.
他人の成功を妬んで卑劣な噂を流した。
He spread despicable rumors out of jealousy over someone else's success.
卑劣な手段で契約を奪うのは許されない。
It's unacceptable to take a contract by underhanded means.
彼のやり方は卑劣だと感じた。
I felt his methods were despicable.