Definition from Wiktionary, the free dictionary
bluebottle (plural bluebottles)
- Any of various blowflies of the genus Calliphora that have an iridescent metallic-blue body and make a loud buzzing noise whilst flying.
- Any of various marine creatures of the genus Physalia, such as Physalia physalis, the Portuguese man-of-war.
- Centaurea cyanus, a plant that grows in grain fields, with blue flowers resembling bottles.