To grind is defined as to crush, reduce to a powder using friction or to rub two surfaces together forcefully.(verb)
An example of to grind is using a mortar and pestle to turn cumin seeds into cumin powder.
See grind in Webster's New World College Dictionary
Origin: ME grinden < OE grindan < IE *ghrendh < base *ghren-, to rub away, pulverize > ground
See grind in American Heritage Dictionary 4
verb ground ground (ground), grind·ing, grinds verb, transitive
Origin: Middle English grinden
Origin: , from Old English grindan; see ghrendh- in Indo-European roots.
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