M / Mattārĭus
noun

Mattārĭus

gen. Mattārĭi · gender masculine · decl. 2nd
one who sleeps on a mat
one who sleeps on a mat (late Lat.), a name applied by the orthodox to a sect of Manichæans: quia in mattis dormiunt, Mattarii appellantur, Aug. contr. Faust. 5, 5; id. de Haeres. 46.