The Seven Luminaries, Five Elements, and Names of the Planets in Mongolian

As is pointed out elseshere, the Japanese days of the week are named after the Seven Luminaries (七曜 shichiyō), a term referring to the Sun, the Moon, and the five visible planets. The term was originally borrowed from Chinese 七曜 qīyào. Under the influence of Chinese culture, the Mongolians call the Seven Luminaries долоон гариг doloon garig or долоон гараг doloon garag 'the seven planets'. According to an Inner Mongolian dictionary, the Seven Luminaries can be systematised as follows, with at least four sets of names:

Planet (element/phase)	Tibetan	Indian	'Stars'	Mongolian	Chinese	Readings (Mandarin, Japanese, Korean)
Sun	ням nyam	адъяа adya	наран од naraŋ od	наран naraŋ	日曜	Ch: rìyào Ja: nichiyō Ko: illyo
Moon	даваа davaa	сумъяа sumya	саран од saraŋ od	саран saraŋ	月曜	Ch: yuèyào Ja: getsuyō Ko: wollyo
Mars (fire)	мягмар myagmar	ангараг aŋgarag	гал од gal od	улаан нүдэн ulaaŋ nüdeŋ	火曜	Ch: huǒyào Ja: kayō Ko: hwayo
Mercury (water)	лхагва lkhagv	буд bud	усан од usaŋ od	үлэмж ülemj	水曜	Ch: shuǐyào Ja: suiyō Ko: suyo
Jupiter (wood)	пүрэв pürev	бархасбадь barkhasbad'	модон од modoŋ od	гадсан gadsaŋ	木曜	Ch: mùyào Ja: mokuyō Ko: mogyo
Venus (gold/metal)	баасан baasaŋ	сугар sugar	алтан од altaŋ od	цолмон tsolmoŋ	金曜	Ch: jīnyào Ja: kin'yō Ko: geumyo
Saturn (earth)	бямба byamb	санчир saŋchir	шороон од shorooŋ od	ховдог эмгэн khovdog emgeŋ	土曜	Ch: tǔyào Ja: doyō Ko: toyo

The first two columns show the familiar Tibetan and Indian names, as used in the days of the week. The third column is an exact equivalent of the Chinese names, consisting of an element/phase plus the word од od 'star'. The names in sequence mean 'sun star; moon star; fire star; water star; wood star; gold star; earth star'.

The fifth column is a rather curious one, starting with the sun and the moon, then cycling through some well-known as well as obscure terms. The name for Mars means 'red eye', that for Mercury in the dictionary is given as 'huge', and that for Jupiter is more normally found in алтан гадасан altan gadasan 'golden gadasan' or Pole Star. Цолмон tsolmon is a very common word used in Mongolian names. The final name, ховдог эмгэн khovdog emgeŋ literally means 'voracious old woman'.

The Chinese names of the five visible planets are based on the Five Elements or Five Phases. In Mongolian, the five elements or phases are (note that the traditional order of the five elements is not the same as that of the planets:

Element	Mongolian (incl. Buryat)	Chinese character	Chinese (Mandarin) and Japanese reading
Metal	төмөр tömör (Buryat: Түмэр tümär)	金	Ch: jīn Ja: kin Ko: geum
Wood	мод mod (Buryat: модон modon)	木	Ch: mù Ja: moku Ko: mog
Water	ус us (Buryat: уһан uhan)	水	Ch: shuǐ Ja: sui Ko: su
Fire	гал gal (Buryat: гал gal)	火	Ch: huǒ Ja: ka Ko: hwa
Earth	шороо shoroo (Buryat: шорой shoroj)	土	Ch: tǔ Ja: do Ko: to

For each of these, the meaning of the Mongolian term exactly parallels that of the Chinese. However, there is one element/phase that is not normally used in the names of the planets in Mongolian: the element/phase төмөр tömör 'iron' is dropped in favour of алтан altaŋ as the name of Venus.

In scientific use, the planetary names in Mongolian now usually use the Indian names:

The last two names mean 'king of heaven' and 'king of the sea' respectively. ван vaŋ is from the Chinese word 王 wáng 'king'. In Inner Mongolia, other names corresponding to the five elements or phases are also used.