Difference between Gritstone and Grit

Gritstone

Part of speech: noun

Definition: A form of sedimentary rock, similar to sandstone but coarser.

Grit

Part of speech: verb

Definition: To clench, particularly in reaction to pain or anger; apparently only appears in gritting one's teeth.To cover with grit.

Part of speech: noun

Definition: Collection of hard small materials, such as dirt, ground stone, debris from sandblasting or other such grinding, swarf from metalworking.Inedible particles in food.A character trait that means to have courage, fearlessness, or guts.Husked but unground oats.

Example sentence: I like things that make you grit your teeth. I like tucking my chin in and sort of leading into the storm. I like that feeling. I like it a lot.