Reconstruction:Proto-Sino-Tibetan/(s/z)a-j

• Proto-Sino-Tibetan: ?
  • Proto-Tibeto-Burman: *sa-y ⪤ za-y (Matisoff, STEDT); *z(l)a-y (Matisoff, 2003); *sa (Matisoff, 2003)

The palatal coda is perhaps a diminutive suffix (Matisoff, 1995).

Proto-Tai *zwɯəjᴬ (“sand”), whence Thai ทราย (saai, “sand”), Lao ຊາຍ (sāi, “sand”) and Zhuang saiz (“sand”), is a loan either from Old Chinese 沙 (OC *sraːl, *sraːls, “sand”) or from this Proto-Sino-Tibetan root itself.

Dunes of the Taklamakan desert.

*(s/z)a-j

1. earth, sand, soil

• Old Chinese: 沙 /*sˤraj/ (B-S), /*sraːl, sraːls/ (ZS) ("sand")

  →   Thai:  ทราย ("sand")
        Lao:  ຊາຍ ("sand")

  • Middle Chinese: 沙 sræ (/ʃˠa/) ("sand")

• • →   Japanese:  沙 (しゃ, ​sha)
          Korean:  사 (沙, sa)
          Vietnamese:  sa, xa (沙)

• • • Modern Mandarin
      • Beijing: 沙 (shā, /ʂa̠⁵⁵/, “sand”)
    • Yue
      • Cantonese: 沙 (/sɑː⁵⁵/, “sand”)
  • Min Nan
    • Xiamen: 沙 (/sa⁴⁴/, “sand”)
• Tangkhulic
  • Tangkhul: si (“sand”)
• Sal
  • Jingpho [Kachin]: zai-bru (“sand”)
• Himalayish
  • Tibeto-Kanauri
    • Bodic
      • Tibetan
        • Written Tibetan: ས (sa, “sand, earth, ground”)
• Tangut-Qiang
  • Northen Tangut
    • Tangut: 𗉺 (śia, /*ɕi̯ɑ⁵⁵/, “sand”) (Possibly a loan from Chinese; often used for its phonetic value, e.g. 𗉺𗐺 (śia mẽ, “shaman”)[1])
• Lolo-Burmese-Naxi
  • Lolo-Burmese:

    *say² ("sand")

    • Burmish
      • Written Burmese: သဲ (sai:, “sand”)
    • Loloish
      • Central Loloish
        • Lahu: šɛ̂ (“sand”)

• *ts(j)a (“earth, ground”)
• *r-ka (“earth, ground, soil”)
• *m-lej ~ m-ləj (“earth, ground, mud; country”)