Reconstruction:Proto-Sino-Tibetan/b-jəw-n ~ bwəj

• Proto-Sino-Tibetan: *yəw+śɑ ("animal (prefix) + rat") (Chou, 1972)
  • Proto-Tibeto-Burman: *b-yəw-n ("rat / rabbit / hare"), *bwəy ("bamboo rat") (Matisoff, STEDT); *b-yuw, *b-yəw (Benedict, 1972; Chou, 1972)

The *-n here is said to function as a collective plural suffix (STC).

*b-jəw-n ~ bwəj

1. rat, bamboo rat
2. rabbit, hare

• Chepangic:
  • Chepang: युः (yuʔ, “mouse, rat”)
• Old Chinese: 鼬 /*lu-s/ (?) (B-S, unlisted), /*lɯwɢs/ (ZS) (“weasel”); 㕙 /*sʰlun/, /*sʰluns/ (ZS) (dialectal) (“hare”) (as in 東郭逡 / 东郭逡, 東郭㕙 / 东郭㕙) (per Matisoff, Schuessler)
  • Middle Chinese: 鼬 /jɨuH/; 㕙 /tsʰiuɪn/
    • Mandarin:
      • Beijing: 鼬 (yòu) /i̯oʊ̯⁵¹/; 㕙 (qūn, jùn) /t͡ɕʰyn⁵⁵/, /t͡ɕyn⁵¹/
• Kamarupan
  • Proto-Kuki-Chin: *yuu
    • Central Chin
      • Mizo: sa-zu (“rat”) (first element from *sja-n), bui (“bamboo rat”)
    • Khomic
      • Khumi Chin: bäjö (“rat”), jung (“rabbit”)
• Himalayish
  • Tibeto-Kanauri
    • Bodic
      • Tibetan
        • Tibetan: བྱི་བ (byi ba, “mouse, rat”), བྱིའུ (byi'u, “shrew mouse, baby bird, alpine hare”), ཡོས (yos, “hare (in year name)”)
          • Dzongkha: བྱི་ཙི (byi tsi, “rat, mouse”)
• rGyalrongic
  • East rGyalrongic
    • Situ: pəɟu (“mouse, rat”)
• Jingpho-Asakian
  • Jingpho
    • Jingpho: yu (“rat”)
• Lolo-Burmese
  • Burmish
    • Burmese: ယုန် (yun, “rabbit, hare”), ပွေး (pwe:, “mole, bamboo rat”)
  • Loloish: /*pi²/ ("bamboo rat") (Bradley, 1979)
    • Central Loloish
      • Lisu (Southern): ꓑꓺ ꓦꓯꓹ (pɑ̱ h̃æ̌, “bamboo rat”)
• Proto-Karen: *jowᴮ (“mouse, rat”) (Luangthongkum, 2013)
  • S'gaw Karen: ယုၢ် (yu̱, “mouse; rat”)
  • Western Pwo: ယူ (“rat”)

• *rwak (“rat”)