hazardous

Etymology

It is formed from English hazard + -ous,^[2][3][4] perhaps after Middle French hasardeux (“risky”), recorded from 1540;^[2] SOED, the Oxford Dictionary of English and Merriam-Webster take it straight from the French word, which is formed from hasard (“chance”).^[5][6][7] The noun hazard first named a game of dice, and goes back to hasard, probably ultimately from Arabic اَلزَّهْر (az-zahr, “the die”),^[2][3][8] although that word is not found in classical Arabic, and Etymonline calls the origin uncertain.^[2][3]

Earliest recorded meaning

Full of risk or danger; risky: 1549, in a letter in the Scottish correspondence of Mary of Lorraine.^[2] Etymonline dates the word to the 1580s, when it meant "venturesome", and the sense "perilous" to the 1610s;^[3] Merriam-Webster's first date is 1585.^[7]

Semantic evolution

The adjective followed its noun, whose sense had moved in French from the gambling game to the chances of the game and then to the chances of life.^[3] Besides "risky" (1549), it was used of people for "given to taking risks, reckless" from 1560, a sense the Shorter Oxford marks as obsolete since the 17th century,^[2][5] and for "depending on chance, like the game of hazard" from 1585.^[2][7] Johnson (1755) defined it as "dangerous; exposed to chance".^[9] In Rutland and Surrey dialect it kept the meaning "uncertain, depending on chance", as of a crop.^[10] The sense "harmful to health or to the environment", now common of substances, is recorded from 1748.^[2]

Timeline

• 1549 – fraught with risk; dangerous.^[2]
• 1560 – of a person, reckless, venturesome.^[2][5]
• 1585 – depending on chance.^[2][7]
• 1748 – harmful to health or the environment; toxic.^[2]

Modern meaning

Adjective

1. Involving great risk or danger: a hazardous climb along the cliff edge.
2. Harmful to people's health or to the environment; toxic: hazardous chemicals.
3. Depending on chance; aleatory.

Word family

• hazardously
• hazardousness
• ultrahazardous
• unhazardous

Related words

• hazard
• biohazard

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k l Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d e Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
5. ^ a b c Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
6. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
7. ^ a b c d Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
8. ^ The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
9. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
10. ^ Wright, Joseph, ed. (1898–1905), The English Dialect Dictionary, 6 vols., Oxford: Henry Frowde; via EDD Online 4.0, University of Innsbruck (CC BY 4.0)