bootleg (n.)

also boot-leg, "upper part of the leg of a boot," 1630s, from boot (n.1) + leg (n.). As an adjective in reference to illegal liquor, 1889, American English slang, from the trick of concealing a flask of liquor down the leg of a high boot. Before that the bootleg was the place to secret knives and pistols. Extended to unauthorized music recordings, etc., by 1957.

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Definitions of bootleg from WordNet
bootleg (v.)
sell illicit products such as drugs or alcohol;
They were bootlegging whiskey
bootleg (v.)
produce or distribute illegally;
bootleg tapes of the diva's singing
bootleg (n.)
whiskey illegally distilled from a corn mash;
Synonyms: moonshine / corn liquor
bootleg (n.)
the part of a boot above the instep;
bootleg (adj.)
distributed or sold illicitly;
Synonyms: black / black-market / contraband / smuggled