Definition of betrayal | Bee Dictionary of English

Judas, his betrayal led to the downfall obviously of Jesus.
Sexual politics gives way to political horror during the Cultural Revolution, when personal betrayal may be the one way to stay alive.
The betrayal of a loyal associate maybe? A brutal mob murder? Please.

Blood Brothers
Brotherhood, the high octane Showtime family drama of Irish gangsters, politicians, blood and betrayal, set in the back streets and boardrooms of Providence, has returned to the airwaves. If you've been missing The Sopranos, this is definitely the best way to get a mob drama fix.
June 27, 2013 - Irish Central
10 books about James "Whitey" Bulger
He's been charged with 19 counts of murder. He's also facing assertions that he was an FBI informant before he skipped town and spent 16 years living on the lam. The trial of reputed Boston mob boss James "Whitey" Bulger is full of drama, intrigue, and tales of death and betrayal. Interested in learning more about Bulger? You're in luck. He's been written about often over the years. Here are 10 ...
June 26, 2013 - The Christian Science Monitor
Women's rights at stake if Afghan-Taliban peace negotiations collapse
HRW's Afghanistan researcher Heather Barr said abandoning women's rights in Afghanistan would be a betrayal by the international community.
June 26, 2013 - GlobalPost

Pope Benedict XVI in The Republic
Then at World Youth Day 2008, he said, "I am deeply sorry for the pain and suffering the victims have endured. ...... These misdeeds, which constitute so grave a betrayal of trust, deserve unequivocal condemnation."
President Bush in CNN International
Every peaceful nation in the region has an interest in opposing Iran's nuclear weapons ambitions,Bush said. "To allow the world's leading sponsor of terror to gain the world's deadliest weapon would be an unforgivable betrayal of future...
Ayman al-Zawahri in guardian.co.uk
The tsar of Washington invited 16 Arab countries ...... to sit in one room, at one table with the Israelis,Zawahiri said, adding that the conference "witnessed the betrayal deals to sell Palestine".