obrubesco
Could not find obrubescas in Logeion dictionaries.
obrubescas Verb: present active subjunctive 2nd singular of obrubesco
ob-rubēsco, ere, über und über erröten, frons aut pudore obrubescit, aut timore pallescit, Augustin. serm. 107, 7.
obrŭbēscō, ĕre, intr., rougir : Aug. Serm. 107, 7.