What is to rub roughly or harshly, as one body against another, causing a harsh sound; as, to grate the teeth; to produce (a harsh sound) by rubbing. On their hinges grate Harsh thunder. Milton called?

grate — To rub roughly or harshly, as one body against another, causing a harsh sound; as, to grate the teeth; to produce (a harsh sound) by rubbing. On their hinges grate Harsh thunder. Milton. (Webster's 1913.)

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