Abstract Tangut, a mediaeval Qiangic language (Sino-Tibetan family) distinguishes three grades (děng 等). The traditional Sofronov-Gong reconstruction of this distinction postulates different degrees of medial yod: Grade I {-Ø-}, Grade II {-i-}, Grade III {-j-}. The yods, however, are not supported by the transcriptional evidence. Based on cognates between Tangut and Rgyalrongic languages, this study proposes the uvularization hypothesis: Tangut syllables have contrastive uvularization. Grade I/II syllables are uvularized, while Grade III syllables are plain. For phonological velars, uvularized syllables trigger a uvular allophone, while plain syllables trigger a velar allophone. Tangut uvularization is an instance of a common typological feature in Qiangic languages, that of Guttural Secondary Vocalic Articulations (GSVA), variously termed uvularization, velarization, tenseness, or Retracted Tongue Root (RTR). Recognizing Tangut grades as a case of Qiangic GSVA has far-ranging potential consequences for Sino-Tibetan comparative linguistics.