(informal) By a large margin; with great significance.

(idiomatic) A person with a reputation of importance or power. / (idiomatic) A rare and significant chance to achieve fame or success.

(slang) Prison, jail. / (slang, obsolete) The workhouse. / A religious building of the Delaware Indians, representing the cosmos. / Used other than figuratively or idiomatically: see big, house.

(US, slang) San Quentin prison.

(slang, street name) The drug heroin.

(mathematical analysis) Upper bound function; see big O notation. / (slang, usually preceded by "the") Orgasm.

(baseball) A home run.

(military) A large artillery gun or one of the largest-caliber naval guns (as on a battleship).

(computing) Storing the most significant byte of a multibyte number at a lower address than the least significant byte; that is, "big end" first.

(idiomatic) The mouth of someone who talks too much, especially by making exaggerated claims or by inappropriately revealing information.