(ש"ע) שמיר לשיוף ומירוק

n. powder used for grinding and polishing

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Noun
1. a hard gary-black mineral consisting of corundum and either hematite or magnetite; used as an abrasive (especially as a coating on paper)
(hypernym) mineral
(substance-holonym) emery paper, sandpaper
(substance-meronym) corundom, corundum

(n.)
Corundum in the form of grains or powder, used in the arts for grinding and polishing hard substances. Native emery is mixed with more or less magnetic iron. See the Note under Corundum.
  

meyer