(software, testing) Any form of testing in which knowledge of the internals of the system being tested are unknown and unimportant.

Alternative form of post office box and PO box.

(simile, slang) Very stupid.

(soccer) penalty box

(idiomatic) To create a predicament or problem for oneself; to do something that leaves one with no good alternatives or solutions.

(idiomatic, politics) To commit fraud in an election by depositing extra or otherwise illegitimate ballots into the container holding voters' ballots, in an attempt to predetermine the outcome.

present participle of stuff the ballot box

plural of box-drawing character

(computing, typography) A text character used for creating geometric frames and boxes.

(slang) Completely mad; insane; crazy.