methane

noun

Etymology: From methyl + -ane.

1. The simplest aliphatic hydrocarbon, CH₄, being a constituent of natural gas, and one of the most abundant greenhouse gases.

   “Cattle emit a large amount of methane.”

   “Methane, an invisible, odorless gas that makes up more than 95% of natural gas fuel, can be as much as 80 times more potent as a global warmer per given unit than CO₂, which is more plentiful in the atmosphere. While there are less emissions than CO₂, methane lasts around 12 years, while CO₂ lingers for centuries.”

2. Any of very many derivatives of methane.