1. noun /mæʃ/
a) A mass of mixed ingredients reduced to a soft pulpy state by beating or pressure; a mass of anything in a soft pulpy state.
b) In brewing, ground or bruised malt, or meal of rye, wheat, corn, or other grain (or a mixture of malt and meal) steeped and stirred in hot water for making the wort.
2. verb /mæʃ/
a) To convert into a mash; to reduce to a soft pulpy state by beating or pressure; to bruise; to crush; as, to mash apples in a mill, or potatoes with a pestle. Specifically (Brewing), to convert, as malt, or malt and meal, into the mash which makes wort.
to mash on a bicycle pedal
b) To press down hard (on).
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