Simple past tense and past participle of grate.(verb)
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Use "grated" in a sentence
"Another Instance of the strange _loosening_ nature of a violent jarring Motion, or a strong and nimble vibrative one, we may have from a piece of _iron_ grated on very strongly with a _file_: for if into that a pin _screw'd_ so firm and hard, that though it has a convenient head to it, yet it can by no means be _unscrew'd_ by the fingers; if, I say, you attempt to unscrew this whilst _grated on by the file_, it will be found to undoe and turn very _easily_."
"But the constant flux of plants growing, dying back and growing again grated against her nerves."
"Mix all ingredients together, stirring in grated cheese last."