obatresco
ŏb-ātresco, ĕre, v. inch. n. [obatratus],
- to become black, Firm. Math. praef.
obātrēsco, ere (ob u. ater), überschwärzt werden, Iul. Firm. math. praef. p. 1 ed. Basil. (1551).
ŏbātrēscō, ĕre (ob, ater), intr., devenir noir : Firm. Math. 1, præf., 4.