chemtrail
n.— «The chemicals are deposited into the sky by jets, and they leave trails that resemble those left by planes when flying at certain altitudes. The trails that we are used to seeing, which are caused by condensation, are called “contrails.” However, those that contain the chemicals are named “Chemtrails.”» —“Global Warming report—Keeping you guessing!” by Ian Brockwell American Chronicle Apr. 2, 2007. (source: Double-Tongued Dictionary)