swear blind

(redirected from swear up and black and blue)

swear blind

To make a very serious, solemn pledge, especially that one is telling the truth. Janet has sworn blind that she wasn't the one to betray me, and I believe her.
See also: blind, swear

swear up and down

To make a very serious, solemn pledge, especially that one is telling the truth. Janet has sworn up and down that she wasn't the one to betray me, and I believe her.
See also: and, down, swear, up

swear blind

BRITISH or

swear up and down

AMERICAN
If someone swears blind that something is true, they insist that they are telling you the truth. He swore blind that he hadn't taken the money. He swears blind that he bears no grudges against Manchester United for sacking him, but I don't know if I believe him.
See also: blind, swear

swear up and down

AMERICAN
If someone swears up and down that something is true, they insist very strongly that they are telling you the truth. He swore up and down he was going to get the cash and bring it right back. I couldn't get it out of my head that maybe it was all part of his plan, although he swore up and down it wasn't. Note: The usual British expression is swear blind.
See also: and, down, swear, up