Reconstruction:Proto-Sino-Tibetan/s-r(j)ak

• Proto-Sino-Tibetan: *riak/rjiak (Coblin, 1986)
  • Proto-Tibeto-Burman: *s-r(y)ak (Matisoff, STEDT); *ryak (Benedict, 1972)

Schuessler (2007) assigned Chinese 夜 to → *ja (“night”) instead. Benedict (1972) listed Chinese 宿 as a reflex of this root, but the initials and vowels are difficult to reconcile.

*s-r(j)ak

1. night
2. day (24 hours)
3. to spend the night, overnight

• Old Chinese: 夜 (*ɴ.rak-s (B-S), *laːgs (ZS), “night”)
  • Middle Chinese: 夜 (jiaH)

• • →   Japanese:  夜 (や, ​ya)
          Korean:  야 (夜, ya)
          Vietnamese:  dạ (夜)

• • • Modern Mandarin
      • Beijing: 夜 (yè), /i̯ɛ⁵¹/
• Kamarupan
  • Kuki-Chin

    *riak-I, riaʔ-II (“to spend the night; overnight”) (VanBik, 2009)

    • Central Chin
      • Lushai [Mizo]: riak, riah (“to spend the night, to lodge for the night”)
• Himalayish
  • Tibeto-Kanauri
    • Bodic
      • Tibetan
        • Written Tibetan: ཞག (zhag, “day (24 hours)”) (> ཞག་པོ (zhag po, “day (24 hours); night”), ཞག་མལ (zhag mal, “night's lodging”))
• Lolo-Burmese-Naxi
  • Lolo-Burmese

    /*ʔrak/ ("night, spend the night") (Matisoff, 1972)

    • Burmish
      • Burmese: ရက် (rak, “day (24 hours)”)
    • Loloish: *ʔ-rakᴸ (“night”), *C-yakᴸ (“spend the night”) (Bradley, 1979)
      • Northern Loloish
        • Yi (Liangshan): ꉖ (hxot, “(classifier) night”)
      • Central Loloish
        • Lisu (Southern): ꓦꓬꓼ (h̃jà, “(classifier) night”)

• *s-rjak (“oil, fat, grease”)