Lewis & Short

mĕrācŭlus (also sync., meraclus), a, um, adj. dim. [meracus], pretty pure, with very little mixture (post-Aug.): meraclo se percussit flore Libyco (al. meraco), Plaut. Cas. 3, 5, 15: vinum, Cels. 3, 19; Plin. 20, 19, 80, § 209.