Synonyms for Grain (same or very similar meaning)
WordNet sense 1 (a weight unit used for pearls or diamonds: 50 mg or 1/4 carat):
metric grain
WordNet sense 2 (dry seedlike fruit produced by the cereal grasses: e.g. wheat, barley, Indian corn):
caryopsis
WordNet sense 3 (foodstuff prepared from the starchy grains of cereal grasses):
cereal, food grain
WordNet sense 4 (thoroughly work in):
ingrain
WordNet sense 5 (form into grains):
granulate
From the ODE community, based on WordNet
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