noun Astronomy. a celestial body moving about the sun, usually in a highly eccentric orbit, consisting of a central mass surrounded by an envelope of dust and gas that may form a tail that streams away from the sun.
Origin:
1150–1200; Middle English comete < Anglo-French, Old French < Latin comētēs, comēta < Greek komḗtēs wearing long hair, equivalent to komē-, variant stem of komân to let one's hair grow (derivative of kómē hair) + -tēs agent suffix
Related formscom·et·like, adjective