Lethargus, lethargi, m. g. Cels. A drousie and forgerfull sickenesse rising of impostinnation of colde fleugme putrifted, especially in the hinder parte of the braine, whereby memorie and reason almost vtterly perisheth and the power sensitiue is greatly annoyed. In it men commonly forget their owne names, & also to shut their mouthes aster they haue gaped, ne can they by any meanes be staped from sleeping.Grauis lethargus. Lucret. Grandr lethargo oppressus. Horat. Pressus graui lethargo. Quint.
Lewis and Short: Latin dictionary
lēthargus, a, um, adj., Gr. lh/qargos, drowsy, lethargic: morbus, Plin. 23, 1, 6, 10; Schol. Juv. 6, 613.—Esp. as subst.A. lēthargus, i, m. (sc. morbus), drowsiness, lethargy (in Cels. 3, 20, written as Greek): lethargo grandi est oppressus, Hor. S. 2, 3, 145; cf.: gravi lethargo oppressus, Serv. Sulp. ap. Quint. 4, 2, 106: olfactoriis excitatur, Plin. 30, 11, 29, 97: in lethargum vergere, id. 32, 10, 38, 116.—(b).Plur.: ocimum facit lethargos, Plin. 20, 12, 48, 119; 28, 8, 29, 116.—B. (Sc. homo.) A lethargic person, Cael. Aur. Acut. 2, 9, 37 sqq.