*braguz

De (Vaan 2002) does an extensive analysis of the reflexes of this term. Likely from ablauting pre-Germanic *bregus / *brogus, a Verner alternate of Proto-Germanic *brehaną (‘to flicker, glitter; light up; blink’), from Proto-Indo-European *bʰreḱ- (‘to shine’). Reconstructed as a u-stem based on the Old English, where u-stems formed a small, unproductive, and receding class, of typically high-frequency archaisms. It is unlikely that Old English would have shifted it into this class from another larger class such as the a-stems or i-stems, whereas these nouns were often shifted to the latter in Old Norse. There are possible alternate forms of *bragiz, *bragô, *bragz based on the Old Norse reflexes. Related to *bregdaną (‘to flicker, flutter, jerk, tug (on), twitch, flinch, move, swing’).