Phosphorus

Phosphorus: As a proper noun, an old name Venus, especially seen just before sunrise in the morning sky.

Phosphorous is also a chemical element.  It highly reactive.  When phosphorous comes into contact with the air, it burns.

It exists in white (or sometimes yellow), red, and black forms. 

Phosphorus is a key component in matches, fireworks, and fertilizers.  It is also used to protect metal surfaces from corrosion.

Both words, the old word for planet, and the word for the chemical, describe their objects well.  After all, both “bear” light.

From Greek φωσφορος (phōsphóros): bearer of light.  The Greek word derives further form two Greek words, φῶς (phôs): light, and φέρω (phérō) meaning, I carry.