Definition of bit bucket:
(n) :
(by extension, humorous, slang) An imaginary domain that accepts lost, discarded, or useless digital data that does not reach its intended destination, such as data lost in transmission or due to errors; the notional resting place of lost or missing digital information.
(v) :
(slang, humorous, computing, transitive) To delete.
(n) :
(historical) A container for holding chad (“small punched-out pieces of paper”) from paper tape or punch cards used with teleprinters, early computers, and other machines.