bag Look up bag at Dictionary.com
early 13c., bagge, from O.N. baggi or a similar Scandinavian source, perhaps ultimately of Celtic origin. Disparaging slang for "woman" dates from 1924 (though various specialized senses of this are much older). Meaning "person's area of interest or expertise" is 1964, from Black Eng. slang, from jazz sense of "category," probably via notion of putting something in a bag. To be left holding the bag (and presumably nothing else), "cheated, swindled" is attested by 1793. Many fig. senses are from the notion of the game bag (late 15c.) into which the product of the hunt was placed; e.g. the verb meaning "to kill game" (1814) and its colloquial extension to "catch, seize, steal" (1818).