sell out (someone/something)

to stop being loyal to someone or something.

He accused Congress of selling out the American people to lawyers who opposed the bill.

I could sell you all out and go straight to the police with this information.

Usage notes: often money is the advantage that is gotten:

Anyone who would sell out his own country for money deserves to go to prison for life.

• bear down on someone
• bear down on something
• beard someone in den
• beard someone in their den
• be a recipe for
• be a recipe for disaster
• be a recipe for [disaster/happiness/success etc.]
• be a recipe for happiness
• be a recipe for success
• bear fruit
• bear hug
• bear in mind
• be armed to the teeth
• bear out
• bear out something
• bear something in mind
• bear testimony to
• bear testimony to something
• bear the brunt of
• bear the brunt of something
• bear up
• bear with
• bear with someone
• bear with something
• bear witness to