What is a 3 letter word that starts with gas?

The only three-letter word that starts with "gas" is gas. Gas is a state of matter that is typically neither a solid nor a liquid, but rather a highly compressible gas. It is composed of particles that move rapidly in all directions and have very little intrinsic structure. The most common forms of gas are oxygen and nitrogen, which make up the majority of Earth's atmosphere, but there are many other types of gas as well, including carbon dioxide, hydrogen, methane, and helium. Gas can be used for a wide range of purposes, including heating and cooking, transportation, and power generation. However, gas emissions also contribute to air pollution and climate change, and many scientists and policymakers are working to find cleaner, more sustainable alternatives to traditional fossil fuels.