Emily Dickinson Lexicon

MUD, n. [D. modder; G. moder. See Mother. Εκ του αυτου συμπλοκης του πνευματος εγενετο μωτ. Τουτο τινες φασιν ιλυν, οιδε ὑδατωδους μιξεως σηψιν. Mot, id est, mod; Phœnices ita scribebant. Bochart, Phœn. Lib. 2, Cap. 2. This is said to be a fragment of Sanchoniathon's Phenician history, translated by Philo and preserved by Eusebius. Thus Phenician word mod, μωτ, rendered in Gr. ιλυς, is precisely the English mud, the matter, material or substance of which, according to the ancients, all things were formed. See Castel. Col. 2010, and the word Mother. Plutarch, de Iside, says the Egyptians called Isis muth, that is, mother. This is a remarkable fact, and proves beyond controversy the common origin of the Phenician, Celtic and Teutonic nations. Mud may perhaps be named from wetness, and be connected with L. madeo, Gr. μυδαω; W. mwydaw, to wet.]

Moist and soft earth of any kind, such as is found in marshes and swamps, at the bottom of rivers and ponds, or in highways after rain.