TgJ Is6:13 :וִיתוּבוּן וִיהוֹן לְצָרָבָא‏ : they will return and become something to burn up [MT וְשָׁבָה וְהָיְתָה לְבָעֵר] †
See the entire entry for ṣrb vb. to be scorched

TgJ Is6:13 :דָמַן לְיַבִישִין וְעַד כְעַן אִינוּן רַטִיבִין לְקַייָמָא מִינְהוֹן זַרעָא‏ : they seem dry but still are moist enough to establish offspring from them
See the entire entry for raṭṭīḇ adj. moist