section_path: Names and etymology
section_name: Names and etymology
paragraph_text: Names and etymology
  
  The English proper name for Earth's natural satellite is typically written as Moon, with a capital M. The noun moon is derived from Old English mōna, which stems from Proto-Germanic *mēnōn, which in turn comes from Proto-Indo-European *mēnsis 'month' (from earlier *mēnōt, genitive *mēneses) which may be related to the verb 'measure' (of time).
  
  Occasionally, the name Luna / ˈ l uː n ə / is used in scientific writing and especially in science fiction to distinguish the Earth's moon from others, while in poetry "Luna" has been used to denote personification of the Moon. Cynthia / ˈ s ɪ n θ i ə / is a rare poetic name for the Moon personified as a goddess, while Selene / s ə ˈ l iː n iː / (literally 'Moon') is the Greek goddess of the Moon.
  
  The English adjective pertaining to the Moon is lunar, derived from the Latin word for the Moon, lūna. Selenian / s ə l iː n i ə n / is an adjective used to describe the Moon as a world, rather than as a celestial object, but its use is rare. It is derived from σελήνη selēnē, the Greek word for the Moon, and its cognate selenic was originally a rare synonym but now nearly always refers to the chemical element selenium. The element name selenium and the prefix seleno- (as in selenography, the study of the physical features of the Moon) come from this Greek word.
  
  Artemis, the Greek goddess of the wilderness and the hunt, also came to be identified with Selene, and was sometimes called Cynthia after her birthplace on Mount Cynthus. Her Roman equivalent is Diana. The names Luna, Cynthia, and Selene are reflected in technical terms for lunar orbits such as apolune, pericynthion and selenocentric.
  
  The astronomical symbols for the Moon are the crescent and decrescent, for example in M 'lunar mass'.