one

The number 1; a single unit or individual.

Etymology

From Old English ān, from Proto-Germanic *ainaz. This traces to PIE *h₁óynos meaning "one, single, alone." The same root gave Latin ūnus, which produced English "unit," "union," and "universe."

The Journey: *h₁óynosone

PIE~4500 BCE

*h₁óynos

Proto-Germanic~500 BCE

*ainaz

Old English~500 CE

ān

Modern English~1500 CE

one

Cognates Across Languages

These words in other languages descend from the same PIE root *h₁óynos. They are not borrowings but independent inheritances from a common ancestor.

LanguageWord
Greekoínē (ace on a die)
Latinūnus
Gothicains
Sanskritéka-
Old Irishóin
Lithuanianvienas

Did You Know?

The indefinite article "a/an" descends from the same Old English ān "one." Saying "a book" is historically saying "one book."

This word descends from the Proto-Indo-European root *h₁óynos. See the full root page for descendant trees, sound law references, and scholarly discussion.

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