How did mundus come to mean both world and clean?

Question

Basically what's in the title: How did mundus come to mean both world and clean? L&S lists a number of other meanings, but in my knowledge these are two very frequent uses, that do not seem to have much in common.

I have always wondered whether there is any documented history to explain such different meanings. Was it just the fruit of convergent evolution, a complex process of meaning change from a common original meaning, or something different? I find it even funny that with time in Ecclesiastical Latin both meanings came to be close to opposite: the World as the realm of sin and death, and cleanliness as the absense of evil.

---

My research so far:

There is a Proto-IE root related to mundus meaning to adorn, which would explain most of the clean meaning, but I have not found anything for the world part.

Latin also has the words Terra and Universum.

Terra means Earth (as a part of the whole world, as I understand from the first quote to Cicero in L&S, which makes sense to me). It also has a close PIE root with the same meaning. That seems to suggest terra predates mundus.

About universum I do not have so many clues, except that it seems to be a composite of uni+versus, the later having some ancient semantic field related to turning.

Answer 1

It's possible that the identity is a coincidence and that the adjective and the noun are unrelated homophones. De Vaan's etymological dictionary lists the two words as separate entries and does not draw any connection between them.

That said, it seems plausible that there is a relationship, namely that the "world" sense is based on a calque of the Greek word κόσμος. This has the basic meaning of "order", but also means both "ornament, decoration" and "world", just like the noun mundus. (The semantic connection appears to be the idea of the world as a "natural order".) The concepts "clean" and "ornament" are semantically close enough that mundus (adj.) and mundus (n.) could easily be related, and then the latter would have picked up its additional meaning of "world" in imitation of the Greek word. The possibility of Greek influence is supported by the fact that mundus appears to have been a specifically philosophical word for "world", as opposed to a more common term like orbis terrarum. (ETA: as fdb points out, there's a difference in meaning between mundus and orbis terrarum: the former, like Greek κόσμος, means "the universe", while the latter means "the Earth".)

Answer 2

Came across this post wondering about Italian word "immondizia" meaning "garbage" with origin from Latin "im" ("without") + "mundus" ("clean" or "elegant").

"Mundus" reminded me of Lithuanian "mandagus" ("polite"). Of course, being polite is nice and elegant and worldly. If you add the prefix "ne" (meaning "not", similar to "without") you get "nemandagus", or "impolite". Garbage is certainly impolite!

Answer 3

The original Latin word for ‘world’ was orbs. Mundus is a late translation for the Greek word kosmos. This Greek word conveys the idea of order, and order from a Greek point of view means the right measure, symmetry, harmony and beauty. It was so because the world or the universe was thought in Greece to be that way: orderly constructed, harmonious and beautiful. Mundus is something clean and tidy.

It doesn’t offer all the possible meanings which the greek kosmos does, but it was the best translation the Latin language could make.