altitude sickness

noun

: the effects (such as headache, nausea, or swelling of the brain) of oxygen deficiency in the blood and tissues developed at high altitudes having reduced atmospheric pressure see mountain sickness

Examples of altitude sickness 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.
Low oxygen levels at this altitude may cause altitude sickness or breathing problems, so acclimatization is essential. Kathleen Peddicord, Forbes.com, 30 June 2025 On Thursday, June 26, the father of 14-year-old Zane Wach shared an update on the teen's health following an incident two weeks ago, in which Zane began experiencing hallucinations due to what doctors believe was altitude sickness. Charlotte Phillipp, People.com, 29 June 2025 During their 19-hour hike, Ryan said his son began showing signs of altitude sickness, according to NBC affiliate KSNV. Charlotte Phillipp, People.com, 29 June 2025 Talk about some of the challenges of the race, including potentially altitude sickness. Morgan Korn, ABC News, 21 June 2025 See All Example Sentences for altitude sickness

Word History

First Known Use

1901, in the meaning defined above

Time Traveler
The first known use of altitude sickness was in 1901

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Cite this Entry

“Altitude sickness.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/altitude%20sickness. Accessed 26 Jul. 2025.

Medical Definition

altitude sickness

noun
al·​ti·​tude sickness ˌal-tə-ˌt(y)üd- How to pronounce altitude sickness (audio)
: the effects (as nosebleed, nausea, headache, or cerebral edema) of oxygen deficiency in the blood and tissues developed at high altitudes with reduced atmospheric pressure

More from Merriam-Webster on altitude sickness

Last Updated: - Updated example sentences
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