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Number & MeasureGreekEnglish

Monad

/ˈmoʊnæd/noun

An indivisible unit, in philosophy a simple substance without parts.

The Greek roots

μονάς, μονάδος
monás, monádos
unit, single thing
+
μόνος
mónos
alone, single

Literally: a one

The story of the word

Μονάς was the unit, the number one treated as the source from which the others are generated, and Pythagoreans made it the origin of everything. Leibniz took the word in 1714 for the simple mind-like substances he thought the universe consists of, each reflecting the whole and none with windows. Functional programmers borrowed it again in the 1990s for a structure that wraps values, which is how a Pythagorean term ended up in Haskell tutorials.

How it travelled
Ancient Greek → Latin → English
First recorded
17th century

Same family

monasterymonopolymonkmonotone

In a sentence

Leibniz argued that every monad mirrors the whole universe from its own point of view.

Built on the same root

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