put your neck on the line

put (one's) neck on the line

To personally assume or expose oneself to some risk, danger, or responsibility; to imperil oneself or put oneself in harm's way. Look, I'm putting my neck on the line for you here. I could get fired if they find out what we're up to! You have to take some risks to be successful in business and in life, but don't put your neck on the line for no good reason.
See also: line, neck, on, put
Farlex Dictionary of Idioms.

put your neck on the line

mainly BRITISH or

put your ass on the line

AMERICAN, INFORMAL, RUDE
If you put your neck on the line, you do something although it has large personal risks for you. He put his neck on the line to make the movie. I appreciate your putting your ass on the line for me. Note: You can also say that your neck is on the line or your ass is on the line to say that you will be punished or put in a bad situation if something fails. The captain's neck is on the line after this latest defeat. Note: You can also say that someone puts their ass on the line. I'm not gonna put my ass on the line for him.
See also: line, neck, on, put
Collins COBUILD Idioms Dictionary, 3rd ed.
See also:
  • put (one's) neck on the line
  • put neck on the line
  • put yourself on the line
  • put (oneself) on the line
  • stick (one's) neck out
  • stick neck out
  • stick one's neck out
  • stick your neck out
  • put (one's) butt on the line
References in periodicals archive
Denise said: "The slogan for the campaign says it all - 'Don't put your neck on the line - if you find a lump get it checked' - and I would encourage everyone to take 10 minutes out to visit the clinic and get their necks checked."
Thyroid checks