Thanks to its variety of meanings, the word mundus had already aroused the interest of classical authors. It is in fact widely attested throughout the history of the language both as an adjective and as a noun.
The adjective mundus, -a, -um means primarily ‘propre, d’ où soigné, coquet, élégant’ (DELL, 420), but is it also found used in the rural language when the act of cleaning is involved as is proved by the occurrence in this context of the derived verbs commundō, emundō, and by the expression mundus ager. The definition given to the adjective as mundus quoque appellatur lautus et purus (in Festus, cf. DELL, 420) accounts for this particular meaning because we find expressions describing earth ready for farming as humus subacta et pura ‘earth (which has been) worked and cleaned’. The relevance and wide distribution of this meaning of the adjective in the spoken language is made apparent by the occurrence in the Romance languages of numerous derivatives, such as Italian mondo ‘cleaned, purified’ and mondare ‘to husk, thresh, weed’, or French monder ‘to clean by separating something impure’ and émonder ‘to remove dead branches, to lop a tree’.