1. existing in the form of gas; having the properties of gas
2. containing or producing gas

Examples

• Water vapor is the gaseous form of water.
• The gaseous clouds of Jupiter are mostly hydrogen and helium.
• At high temperatures, most substances become gaseous.
• The gaseous emissions from the factory were carefully monitored.
• Oxygen exists as a gaseous element at room temperature.
• The gaseous mixture expanded when heated.
• Scientists studied the gaseous atmosphere of the distant planet.