Definitions from Wiktionary ( )

▸ noun:  A coarse mediaeval coat of defence, especially one made of leather.
▸ noun:  A man.
▸ noun:  (chiefly capitalized) A name applied to a hypothetical or typical man.
▸ noun:  (countable, now chiefly US) A man, a fellow; a typical man; men in general.
▸ noun:  (colloquial) A sailor.
▸ noun:  (slang) A policeman or detective; (Australia) a military policeman.
▸ noun:  (now rare) A manual laborer.
▸ noun:  (Canada, US, colloquial) A lumberjack.
▸ noun:  (India, historical, slang) A sepoy.
▸ noun:  A device or utensil.
▸ noun:  A device for turning a spit; a smokejack or roasting jack.
▸ noun:  Each of a series of blocks in a harpsichord or the earlier virginal, communicating the action of the key to the quill; sometime also, a hopper in a modern piano.
▸ noun:  (obsolete) A support for wood being sawn; a sawhorse or sawbuck.
▸ noun:  A device used to hold a boot by the heel, to assist in removing the boot.
▸ noun:  A mechanical device used to raise and (temporarily) support a heavy object, now especially to lift one side of a motor vehicle when (e.g.) changing a tyre.
▸ noun:  Any of various levers for raising or lowering the sinkers which push the loops down on the needles in a knitting machine or stocking frame.
▸ noun:  (mining, now rare) A wedge for separating rocks rent by blasting.
▸ noun:  (obsolete) A grating device used to separate and guide the threads in a warping machine; a heck box.
▸ noun:  (obsolete) A machine for twisting the sliver as it leaves a carding machine, in the preparation of yarn.
▸ noun:  (electronics) A switch for a jack plug, a jackknife switch; (more generally) a socket used to connect a device to a circuit, network etc.
▸ noun:  A non-tool object or thing.
▸ noun:  (now historical, regional) A pitcher or other vessel for holding liquid, especially alcoholic drink; a black-jack.
▸ noun:  (card games, originally colloquial) The lowest court card in a deck of standard playing cards, ranking between the 10 and queen, with an image of a knave or pageboy on it.
▸ noun:  (bowls) A small, typically white, ball used as the target ball in bowls; a jack-ball.
▸ noun:  (nautical) A small ship's flag used as a signal or identifying device; a small flag flown at the bow of the vessel.
▸ noun:  (UK, regional, now rare, historical) A measure of liquid corresponding to a quarter of a pint.
▸ noun:  (obsolete, slang) A fake coin designed to look like a sovereign.
▸ noun:  (nautical, now rare, historical) A jack crosstree.
▸ noun:  (games) A small, six-pointed playing piece used in the game of jacks.
▸ noun:  (US) A torch or other light used in hunting to attract or dazzle game at night.
▸ noun:  (slang, chiefly US) Money, cash.
▸ noun:  (Canada, US) A strong alcoholic liquor, especially home-distilled or illicit.
▸ noun:  (colloquial, euphemistic) Nothing, jack shit.
▸ noun:  (cricket, slang) The eleventh batsman to come to the crease in an innings.
▸ noun:  (slang, Appalachians) A smooth often ovoid large gravel or small cobble in a natural water course.
▸ noun:  A plant or animal.
▸ noun:  A pike, especially when young.
▸ noun:  (chiefly US) A male ass, especially when kept for breeding.
▸ noun:  Any of the marine fish in the family Carangidae.
▸ noun:  (US) A jackrabbit.
▸ noun:  A large California rockfish, the bocaccio, Sebastes paucispinis.
▸ noun:  Mangifera caesia, related to the mango tree.
▸ noun:  (colloquial) Plant in the genus Arisaema, also known as Jack-in-the-pulpit, and capitalized Jack.
▸ noun:  (colloquial) Spadix of a plant (also capitalized Jack).
▸ noun:  (apparently does not occur standalone for the genus per se) Plant of the genus Emex, also considered synonymous to Rumex, if not then containing two species lesser jack and little jack for Emex spinosa syn. Rumex spinosus, Australian English three-corner jack and prickly jack for Emex australis syn. Rumex hypogaeus.
▸ verb:  (transitive) To physically raise using a jack.
▸ verb:  (transitive) To raise or increase.
▸ verb:  To increase the potency of an alcoholic beverage similarly to distillation by chilling it to below the freezing point of water, removing the water ice crystals that form, and leaving the still-liquid alcoholic portion.
▸ verb:  (transitive, colloquial) To steal (something), typically an automobile; to rob (someone).
▸ verb:  (intransitive) To dance by moving the torso forward and backward in a rippling motion.
▸ verb:  (colloquial, vulgar) To jack off, to masturbate.
▸ verb:  (African-American English, Memphis) To fight
▸ adjective:  (Australia) Tired, disillusioned; fed up (with).
▸ noun:  The edible fruit of the Asian tree (Artocarpus heterophyllus); also the tree itself.
▸ noun:  The related tree Mangifera caesia.
▸ noun:  (slang, baseball) A home run.
▸ verb:  (transitive, slang, baseball) To hit (the ball) hard; especially, to hit (the ball) out of the field, producing a home run.
▸ noun:  A unisex given name from Hebrew, also used as a pet form of John or more rarely, Jacob.
▸ noun:  A surname.
▸ noun:  (colloquial) Jack Daniel's, a brand of Tennessee whiskey.
▸ noun:  An unincorporated community in Coffee County, Alabama, United States.
▸ noun:  An unincorporated community in Dent County, Missouri, United States.
▸ noun:  (informal) A placeholder or conventional name for any man, particularly a younger, lower-class man.
▸ noun:  A jacqueminot rose.
▸ noun:  Ellipsis of Monterey Jack., a type of cheese. [A mild, white American cheese similar to cheddar.]
▸ noun:  (informal, archaic) Ellipsis of Jack Tar., a sailor.
▸ noun:  (informal, archaic) Ellipsis of Jack Rum., a soldier.

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