acetaminophen

noun

acet·​amin·​o·​phen ə-ˌsē-tə-ˈmi-nə-fən How to pronounce acetaminophen (audio)
ˌa-sə-tə-
: a crystalline compound C8H9NO2 that is a hydroxy derivative of acetanilide and is used in chemical synthesis and in medicine to relieve pain and fever

Examples of acetaminophen in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The American Academy of Pediatrics and other medical groups say acetaminophen is safe for children when used correctly and there are no studies linking its use in children to autism. Mary Kekatos, ABC News, 14 Oct. 2025 Parents, Rappaport continued, should be proactive and stock up on essentials—such as a thermometer, acetaminophen or ibuprofen, saline spray and a humidifier—before children get sick. Daniella Gray, MSNBC Newsweek, 14 Oct. 2025 Health authorities around the country were quick to point out that evidence suggests acetaminophen is an effective and safe treatment for pregnant women and poses no risk to an unborn child. Maria Shriver, Time, 9 Oct. 2025 This means that relying on circumcision to estimate acetaminophen use in newborns is flawed, Tager-Flusberg says. Allison Parshall, Scientific American, 9 Oct. 2025 See All Example Sentences for acetaminophen

Word History

Etymology

acet(yl) + amino + phen(ol)

Note: Shortened from N-acetyl-p-aminophenol. Acetaminophen was introduced as a generic name roughly coincident with the introduction of the trademark preparation Tylenol, which was first marketed as "Children's Tylenol Elixir" in 1955 by McNeil Laboratories. Synthesis of the substance, as acetylamidophenol, was first reported in Berichte der Deutschen Chemischen Gesellschaft, 11. Jahrgang (Jan.-Juni, 1878), p. 232-33 (H. N. Morse, "Ueber eine neue Darstellungsmethode der Acetylamidophenole"). Its antipyretic properties were recognized by the German physician Josef von Mering in the 1893 article "Beiträge zur Kenntniss der Antipyretica" (Therapeutische Monatshefte, 7, pp. 577-87)—he also refers to it as acetylamidophenol.

First Known Use

1958, in the meaning defined above

Time Traveler
The first known use of acetaminophen was in 1958

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Cite this Entry

“Acetaminophen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/acetaminophen. Accessed 17 Oct. 2025.

Kids Definition

acetaminophen

noun
acet·​amin·​o·​phen ə-ˌsēt-ə-ˈmin-ə-fən How to pronounce acetaminophen (audio)
: a crystalline compound used in medicine to relieve pain and fever

Medical Definition

acetaminophen

noun
acet·​amin·​o·​phen ə-ˌsēt-ə-ˈmin-ə-fən How to pronounce acetaminophen (audio) ˌas-ət- How to pronounce acetaminophen (audio)
: a crystalline compound C8H9NO2 that is a hydroxy derivative of acetanilide and is used in chemical synthesis and in medicine instead of aspirin to relieve pain and fever

called also paracetamol

see liquiprin, panadol, tylenol

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