macrocosm (n.)

*māk-, Proto-Indo-European root meaning "long, thin." It forms all or part of: emaciate; macro; macro-; macrobiotic; macron; meager; paramecium. It is the hypothetical source of/evidence for its existence is provided by: Greek makros "long, large," mēkos "length;" Latin macer "lean, thin;" Old Norse magr, Old English mæger "lean, thin."

c. 1200, "the universe, the world" (but not popular until 1848, when it was taken as the English equivalent to Humboldt's Kosmos in translations from German), from Latinized form of Greek kosmos "order, good order, orderly arrangement," a word with several main senses rooted in those notions: The verb kosmein meant generally "to dispose, prepare," but especially "to order and arrange (troops for battle), to set (an army) in array;" also "to establish (a government or regime);" "to deck, adorn, equip, dress" (especially of women). Thus kosmos had an important secondary sense of "ornaments of a woman's dress, decoration" (compare kosmokomes "dressing the hair," and cosmetic) as well as "the universe, the world."

Pythagoras is said to have been the first to apply this word to "the universe," perhaps originally meaning "the starry firmament," but it later was extended to the whole physical world, including the earth. For specific reference to "the world of people," the classical phrase was he oikoumene (ge) "the inhabited (earth)." Septuagint uses both kosmos and oikoumene. Kosmos also was used in Christian religious writing with a sense of "worldly life, this world (as opposed to the afterlife)," but the more frequent word for this was aiōn, literally "lifetime, age."

The word cosmos often suggested especially "the universe as an embodiment of order and harmony."

late 12c., mycrocossmos (modern form from early 15c.), "human nature, man viewed as the epitome of creation," literally "miniature world" (applied metaphorically to the human frame by philosophers, hence a favorite word with medieval writers to signify "a man"), from Medieval Latin microcosmus, from Greek mikros "small" (see micro-) + kosmos "world" (see cosmos).

General sense of "a community constituting a world unto itself, a little society" is attested from 1560s, perhaps from French microcosme. A native expression in the same sense was petty world (c. 1600).

Forrþi mahht tu nemmnenn mann Affterr Grikkishe spæche Mycrocossmos, þat nemmnedd iss Affterr Ennglisshe spæche Þe little werelld. ["Ormulum," c. 1175]

And the Anglo-Saxon glossaries have læsse middaneard.