Other forms: grated; grating; grates
When you grate something you rip it to shreds, like a pound of solid cheese that you shred for a recipe.
The verb grate entered the English language in the fourteenth century by way of the French word grater, meaning “to scrape.” Using grate in this sense, you might grate your teeth or grate a carrot, meaning rub or pulverize. By the sixteenth century the word had taken on the additional meaning of “sound harshly” and “annoy.” This evolution makes sense if you think about it: If you’ve ever had anything really annoy you — "grate on your nerves" — it can almost seem as if a cheese grater has been applied to your nerves and is slowly ripping them to shreds.