The Comprehensive Aramaic Lexicon

TgJ Is8:20 :מִכְעַן לֵית לֵיה מַן דְיַשחַר/דְשָחַר/ וְיִבעוֹהִי : from now on he (Israel) does not have anyone to be vigilant and for him to seek

See the entire entry for šhr vb. to be awake