Emily Dickinson Lexicon

MASS, n.² [Sax. mæsa, mæsse; Fr. masse; It. messa; Sp. misa; D. misse; G. and Dan. messe; Sw. messa; Low L. missa. The word signifies primarily leisure, cessation from labor, from the L. missus, remissus, like the L. feriæ; hence a feast or holiday. Laws of Alfred, 39. “Be mæsse dæge freolse.” De festivitate diei festi. See also Laws of Cnute, Lib. 1, 14, and 2, 42. Hence Sax. hlafmæsse, lemmas, bread-feast, and Martin-mas, Michael-mas, Candlemas, Christmas.]

The service of the Romish church; the office or prayers used at the celebration of the eucharist; the consecration of the bread and wine. Lye. Encyc. Wilkins.