one

Etymology

It is inherited from Middle English oon, also on,^[2][3] inherited from Old English ān,^[4][5][6] from Proto-Germanic *ainaz,^[4][7][8] from Proto-Indo-European *oi-no- (“one, unique”).^[4] Its cognates are Old Frisian ān, Old Saxon ēn, Dutch een, Old High German ein, German ein, Old Norse einn and Gothic 𐌰𐌹𐌽𐍃 (ains),^[4][6][5][7] and, in other branches of Indo-European, Latin ūnus, earlier oinos,^[5][8] Old Irish óen and Lithuanian víenas.^[8][9] The Latin word is the source of ounce, union, unit and unique.^[9][10] The unstressed Old English form gave the article an, a,^[11] and the word also lies behind alone, atone, only, once and none.^[9]

Earliest recorded meaning

The numeral "one", a single unit: Barnhart dates Old English ān before 725, and earlier in compounds such as ānmōd (“of one mind, resolute”), about 700.^[6] The Middle English form on is recorded probably about 1150, and the spelling one about 1200, in Vices and Virtues.^[6]

Semantic evolution

The word was originally pronounced as it still is in only, alone and atone.^[4][9] The modern pronunciation with an initial w began in the south-west and west of England, about the 14th century according to Etymonline and before the 15th according to the Oxford Dictionary of English;^[4][12] Tyndale, a Gloucestershire man, spelled it won in his Bible.^[4][11] It was accepted into standard English only in the late 17th century,^[12] and became general about 1700.^[11] In many languages the same word serves as the indefinite article, but in English the numeral became distinct from a, an.^[9] The use as an indefinite pronoun for "people in general" dates from the late 15th century,^[9] influenced by the unrelated French on and Latin homō.^[4][11] From 1828 one was used colloquially for emphasis, as in one hell of a,^[5] and slang has one happy boy from 1917.^[13] The word was briefly used as an ordinal, "first", between about 1384 and 1425.^[5] The verb one, to unite, is recorded from Old English and is now rare.^[5][2]

Timeline

• c. 700 – in Old English compounds, such as ānmōd.^[6]
• before 725 – the numeral, a single unit.^[6] The OED's first quotation is from the Anglo-Saxon Chronicle, under the year 879.^[5]
• c. 1150 – the Middle English form on; the spelling one follows about 1200.^[6]
• 13th century – pronoun, a certain person or thing.^[2]
• c. 1384 – as an ordinal, first (obsolete by 1425).^[5]
• c. 1450 – verb, intransitive, to agree, come to terms.^[5]
• late 15th century – indefinite pronoun, any person, people in general.^[9]
• 1828 – colloquial, one used for emphasis instead of a, meaning “a very” or “an extremely” before an adjective.^[5]
• 1880 – one-night stand, a single performance; the sexual sense follows in 1963.^[4]
• 1906 – one and only, a sweetheart.^[4]

Meanings

Adjective

1. Being a single person or thing; not two or more: one cup of coffee.^[14][15][2]
2. Being a particular person or thing as distinct from another or others: She held the rope with one hand and waved with the other.^[15][2]
3. Some, a certain (time): One morning he simply left.^[15]
4. Undivided, united; the same: They spoke with one voice.^[14]
5. (informal) Used for emphasis, as a very: That was one tough exam.^[5][13]

Noun

1. The cardinal number represented by 1, the first whole number.^[14][2]
2. A single person or thing; a unit.^[14][2]

Pronoun

1. A particular person or thing of a kind already mentioned: If you need a pen, take one.^[15][2]
2. Any person, people in general: One can't please everyone.^[2][9]

Verb

1. (rare) To make into one; to unite.^[2][5][16]

Word family

• one-man
• one-on-one
• all-in-one
• onefold
• oneness
• oneself
• one-shot
• one-to-one

Related words

• none
• once
• alone
• atone
• only
• an
• a
• any
• anon
• eleven
• ounce
• union
• unit
• unique
• unity
• unison

Usage notes

When a phrase headed by one is the subject, as in one of every five machines, the American Heritage Dictionary recommends a singular verb.^[14]

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
3. ^ Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
4. ^ a b c d e f g h i j Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
5. ^ a b c d e f g h i j k l Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
6. ^ a b c d e f g Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
7. ^ a b Kroonen, Guus (2013), Etymological Dictionary of Proto-Germanic, Leiden Indo-European Etymological Dictionary Series 11, Leiden / Boston: Brill
8. ^ a b c Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
9. ^ a b c d e f g h Ayto, John (2005), Word Origins: The Secret Histories of English Words from A to Z, 2nd ed., London: A & C Black
10. ^ Cresswell, Julia (2021), Oxford Dictionary of Word Origins, 3rd ed., Oxford: Oxford University Press
11. ^ a b c d Weekley, Ernest (1921), An Etymological Dictionary of Modern English, London: John Murray
12. ^ a b Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
13. ^ a b Green, Jonathon (2010), Green's Dictionary of Slang, London: Chambers; digital ed. 2016–, https://greensdictofslang.com
14. ^ a b c d e The American Heritage Dictionary of the English Language (1992), 3rd ed., Boston: Houghton Mifflin
15. ^ a b c d Collins English Dictionary (2023), Glasgow: HarperCollins
16. ^ Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press