Antifreeze is that greenish yellow liquid your dad puts in the car. It's ethylene glycol. It keeps the car's cooling engine from freezing. It's done in cold places and it's a tradition that goes from generation to generation. Don't drink it though, or you'll die. It's sweet tasting, but deadly toxic if you drink it.
You: Dad? What's that yucky green stuff you're putting in the car?
Dad: That's antifreeze! Someday you'll follow in my footsteps and winter-proof your car engine.