From an unused root meaning to rake together; a poker (for turning or gathering embers) -- (fire-)brand.
H181. ud
אוּד noun masculine brand, fire-brand (originally perhaps bent stick used to stir fire) ׳א מִשְּׂרֵפָה מֻצָּל Amos 4:11 = ׳א ׳מ מֵאֵשׁ Zechariah 3:2, plural הָעֲשֵׁנִים הָאוּדִים זַנְבוֺת Isaiah 7:4, stumps of smoking firebrands.