A mill is a factory or plant, especially one that's equipped for grinding grain into flour. The facility is a mill, and the machine that does the actual grinding is also called a mill.

When a mill crushes and grinds grain like wheat or corn, you can say it mills flour. Other kinds of mills might mill powder or coffee — and still other mills don't actually grind anything; instead, they manufacture things like steel or paper. If someone "mills around," they wander or move about in a confused way: "The crowd mills around during the concert's intermission." This sense of mill was originally used to describe cattle.

Definitions of mill
  1. noun
    a plant consisting of one or more buildings with facilities for manufacturing
    synonyms: factory, manufactory, manufacturing plant
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    assembly plant
    a factory where manufactured parts are assembled into a finished product
    auto factory, automobile factory, car factory
    a factory where automobiles are manufactured
    a factory where food is canned
    chemical plant
    an industrial plant where chemicals are produced
    foundry, metalworks
    factory where metal castings are produced
    lumbermill, sawmill
    a mill for dressing logs and lumber
    paper mill
    a mill where paper is manufactured
    stamp mill, stamping mill
    a mill in which ore is crushed with stamps
    steel factory, steel mill, steel plant, steelworks
    a factory where steel is made
    factory where workers do piecework for poor pay and are prevented from forming unions; common in the clothing industry
    textile mill
    a factory for making textiles
    armory, armoury, arsenal
    a place where arms are manufactured
    battery, stamp battery
    a series of stamps operated in one mortar for crushing ores
    bell foundry
    a foundry where bells are cast
    cotton mill
    a textile mill for making cotton textiles
    iron foundry
    a foundry where cast iron is produced
    an assembly plant in Mexico (near the United States border); parts are shipped into Mexico and the finished product is shipped back across the border
    quartz battery, quartz mill
    a stamp mill for stamping quartz
    rolling mill
    steel mill where metal is rolled into sheets and bars
    type of:
    industrial plant, plant, works
    buildings for carrying on industrial labor
  2. noun
    machinery that processes materials by grinding or crushing
    synonyms: grinder, milling machinery
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    cider mill
    mill that extracts juice from apples to make apple cider
    coffee grinder, coffee mill
    a mill that grinds roasted coffee beans
    flour mill
    a mill for grinding grain into flour
    a mill for grinding grain (especially the customer's own grain)
    meat grinder
    a mill for grinding meat
    pepper grinder, pepper mill
    a mill for grinding pepper
    a primitive stone mill for grinding corn by hand
    a mill for grinding spices
    tread-wheel, treadmill, treadwheel
    a mill that is powered by men or animals walking on a circular belt or climbing steps
    water mill
    a mill powered by a water wheel
    a mill that is powered by the wind
    type of:
    machines or machine systems collectively
  3. noun
    the act of grinding to a powder or dust
    synonyms: grind, pulverisation, pulverization
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    type of:
    compaction, crunch, crush
    the act of crushing
  4. verb
    grind with a mill
    mill grain”
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    type of:
    bray, comminute, crunch, grind, mash
    reduce to small pieces or particles by pounding or abrading
  5. verb
    roll out (metal) with a rolling machine
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    type of:
    roll, roll out
    flatten or spread with a roller
  6. verb
    produce a ridge around the edge of
    mill a coin”
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    type of:
    make a groove in, or provide with a groove
  7. verb
    move about in a confused manner
    synonyms: mill about, mill around
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    type of:
    move so as to change position, perform a nontranslational motion
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