(dated) rubbish, humbug

(idiomatic) A statement that one will not allow something (most often a firearm or other weapon) to be taken away from one's possession until after one's death. A variant, from my cold dead fingers, is most often used in the US by gun rights advocates.

Alternative form of butter my butt and call me a biscuit

(cryptography) A number which, by its construction, is above suspicion of having hidden properties; used in creating cryptographic functions such as hashes and ciphers.

plural of nothing-up-my-sleeve number

The phrase used in the guessing game I spy.

(idiomatic) added to a promise or a statement to show how serious one was about being honest in what one said

my car has broken down

(idiomatic, vulgar, humorous, offensive) An expression of discontent or aggravation to another party.

(card games) Synonym of beggar-my-neighbor