ngày

See also: ngay, ngáy, ngậy, ngấy, and ŋay

Muong

Etymology

From Proto-Vietic *-ŋiː, from Proto-Mon-Khmer *t₂ŋiiʔ (“day, sun”); cognate with Vietnamese ngày, Khmer ថ្ងៃ (thngay, “day”), Koho töngai (“day”), Pacoh ingay (“day”), Khasi sngi (“day”), Mon တ္ၚဲ (“sun, day”).

Noun

ngày

(Mường Bi) day
(Mường Bi) date
(Mường Bi) daytime

Vietnamese

Etymology

From Proto-Vietic *-ŋiː, from Proto-Mon-Khmer *t₂ŋiiʔ (“day, sun”); cognate with Muong ngày, Khmer ថ្ងៃ (thngay, “day”), Koho töngai (“day”), Pacoh ingay (“day”), Khasi sngi (“day”), Mon တ္ၚဲ (“sun, day”).

The Vietnamese words for "day" and "night" (and their cognates) have the same distribution within Vietic: reflexes of *-ŋiː (“day”) and *teːm (“night”) are only attested in Thổ, Pong and Viet-Muong, i.e. the "innovative Vietic" group, lacking cognates in the generally more conservative languages.

Tonal evidence for a presyllable *t-

The upper register tone in Thổ Cuối Chăm - ŋaj¹ (A1) - shows that there probably was a presyllable with voiceless initial: if the presyllable had been voiced or if this word had been monosyllabic with a nasal onset, the expected tone would have been A2.
The tone of the Vietnamese word is huyền (A2), showing that the presyllable was already lost by the Common Viet-Muong stage, before tones started to develop.

The presence of a presyllable, although it can not be explicitly identified as *t- by Vietic evidence alone, is indicated with a dash *- in the Proto-Vietic reconstruction. This presyllable corresponds to the *t- in other Austroasiatic languages (or some other sound in Northern Austroasiatic in this case: see đêm (“night”) for examples).

All in all, the relationship between Proto-Vietic *-ŋiː and other Austroasiatic words is secure.

Pronunciation

(Hà Nội) IPA^(key): [ŋaj˨˩]
(Huế) IPA^(key): [ŋaj˦˩]
(Saigon) IPA^(key): [ŋa(ː)j˨˩]
Audio (Hà Nội): (file)
Audio (Saigon): (file)

Noun

ngày • (㝵, 𣈜, 𣈗)

a day (period of 24 hours; period from midnight to the following midnight; rotational period of a planet; part of a day period which one spends at one's job, school, etc.)
Synonyms: hôm, bữa

ngày nghỉ ― a day off
day (period between sunrise and sunset)
Antonyms: đêm, tối

ngủ ngày
to sleep by day
a date (that which specifies the time of writing, inscription etc.; point of time at which a transaction or event takes place)