unambiguous

Etymology

It is formed from English un- + ambiguous.^[2][3][4][5] Ambiguous is from Latin ambiguus (“having a double meaning, doubtful”), from ambigō (“to dispute about, waver”), from ambi- (“about”) and agō (“to drive, lead”).^[4]

Earliest recorded meaning

Not ambiguous, clear in meaning: the OED's first record is a letter of Lord Chesterfield of 19 December 1751.^[2][6] Merriam-Webster dates the word to 1743,^[7][8] and Etymonline to the 1630s.^[4]

Semantic evolution

The word has kept its one sense, having a single clear meaning, since the 18th century.^[2][3][7] The adverb unambiguously followed in 1790 in the OED's record,^[6] the late 18th century in the Shorter Oxford's, and the noun unambiguity in the 19th century.^[3]

Timeline

• 1751 – clear in meaning, not ambiguous.^[2] Merriam-Webster gives 1743 and Etymonline the 1630s.^[7][4]

Meanings

Adjective

1. Having only one possible meaning; clear and precise, leaving no doubt: The instructions were short and unambiguous.^{[7][9][10][3]}

Word family

• unambiguously

Related words

• ambiguous
• ambiguity

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
4. ^ a b c d Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
5. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
6. ^ a b Simpson, J. A.; Weiner, E. S. C., eds. (1989), The Oxford English Dictionary, 2nd ed., Oxford: Clarendon Press
7. ^ a b c d Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
8. ^ Merriam-Webster's Collegiate Dictionary (2003), 11th ed., Springfield, Mass.: Merriam-Webster
9. ^ Collins English Dictionary (2023), Glasgow: HarperCollins
10. ^ The American Heritage Dictionary of the English Language (1992), 3rd ed., Boston: Houghton Mifflin