Eucalyptol (also called cineole) is a monoterpenoid colorless liquid, and a bicyclic ether.

[4] In 1870, F. S. Cloez identified and ascribed the name "eucalyptol" to the dominant portion of Eucalyptus globulus oil.

[1] Eucalyptol is an ingredient in commercial mouthwashes,[1] and has been used in traditional medicine as a cough suppressant.

It was even observed that these males would periodically leave their territories to forage for chemicals such as cineole, thought to be important for attracting and mating with females, to synthesize pheromones.

[1] Eucalyptol is generated from geranyl pyrophosphate (GPP) which isomerizes to (S)-linalyl diphosphate (LPP).