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definitions

brown-bag

[broun-bag]
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verb (used with object), brown-bagged, brown-bag·ging.

to bring (one's own liquor) to a restaurant or club, especially one that has no liquor license.
to bring (one's lunch) to work or elsewhere, usually in a small brown paper bag.

verb (used without object), brown-bagged, brown-bag·ging.

to carry one's lunch in a brown paper bag.

adjective

brought to work, usually in a small brown paper bag: a brown-bag lunch.

Idioms

    brown-bag it, to bring one's lunch to work or elsewhere, especially in a brown paper bag.
Related formsbrown-bag·ger, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Word Origin and History for brown-bag
v.

"to bring lunch or liquor in a brown paper bag," 1970, from brown (adj.) + bag (n.). Related: Brown-bagging.

Online Etymology Dictionary, © 2010 Douglas Harper