un·​der·​weight | \ ˌən-dər-ˈwāt How to pronounce underweight (audio) \

Definition of underweight

 (Entry 1 of 2)

: weight below normal, average, or requisite weight



Definition of underweight (Entry 2 of 2)

: weighing less than the normal or requisite amount

Synonyms & Antonyms for underweight

Synonyms: Adjective

Antonyms: Adjective

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Examples of underweight in a Sentence

Adjective the long illness left him frail and underweight
Recent Examples on the Web: Noun The findings showed evidence that children with a vegetarian diet had almost two-fold higher odds of having underweight, which is defined as below the third percentile for BMI. Julie Washington, cleveland, 10 May 2022 The share of survey respondents who were overweight eurozone stocks dropped 48 percentage points to the largest underweight reading for that region since July 2012. Karen Langley, WSJ, 20 Mar. 2022 This underweight is the dry powder that can come back into the stocks. Brendan Ahern, Forbes, 11 Nov. 2021 Remember Hong Kong internet outperforming and India underperforming is the active manager pain trade due to their overweight to India and underweight to China. Brendan Ahern, Forbes, 20 Jan. 2022 Sectoral rotations should tilt toward real estate and health care, while shifting underweight on consumer discretionary. Chris Taylor, Fortune, 20 Jan. 2022 By rating Jumia’s stock as underweight, Holbrook invites investors to be skeptical of Jumia’s pivot being successful. Alexander Onukwue, Quartz, 30 Nov. 2021 Analysts at Wells Fargo cut their recommendation for Allstate from equal-weight to underweight. Joe Wallace, WSJ, 9 Dec. 2021 Luke Holbrook, a Morgan Stanley equity research analyst, changed the bank’s recommendation for Jumia’s stock from neutral (assigned by a former analyst) to underweight, according to The Motley Fool. Alexander Onukwue, Quartz, 30 Nov. 2021 Recent Examples on the Web: Adjective Being underweight can be a sign of malnutrition and can indicate that one’s diet isn’t enough to support appropriate growth, according to the study news release. Kristen Rogers, CNN, 2 May 2022 Saginaw County Animal Care & Control freed the malnourished and underweight dog and treated her injuries. Kelli Bender, PEOPLE.com, 4 Apr. 2022 The fragile colt was weak and underweight, deaf, couldn’t walk on his deformed hooves and was about the size of a housecat. San Diego Union-Tribune, 30 Jan. 2022 The two surviving cows were found to each be about 100 pounds underweight, the report said. Dom Calicchio, Fox News, 18 Dec. 2021 Most of the children ranging in age at the time of their rescue from 2 to 29 were severely underweight and hadn't bathed for months. Danielle Wallace, Fox News, 10 Nov. 2021 The remaining lemur, which the specialists named Luna, was underweight, severely malnourished and deeply depressed. Taylor Pettaway, San Antonio Express-News, 25 Jan. 2022 Analysts suggest being underweight in consumer staples and discretionary, while tilting overweight in energy, health care, and financials. Chris Taylor, Fortune, 20 Jan. 2022 Seventy percent of Playboy playmates were underweight, according to a study that went to the trouble of examining the waist-to-hip ratio in 240 nudie centerfolds. Alex Beggs, Bon Appétit, 10 Jan. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'underweight.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of underweight


1596, in the meaning defined above


1675, in the meaning defined above

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Time Traveler for underweight

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The first known use of underweight was in 1596

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Dictionary Entries Near underweight

under weigh



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Statistics for underweight

Last Updated

24 May 2022

Cite this Entry

“Underweight.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/underweight. Accessed 29 May. 2022.

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More Definitions for underweight


un·​der·​weight | \ ˌən-dər-ˈwāt How to pronounce underweight (audio) \

Kids Definition of underweight

: weighing less than what is normal, average, or necessary


un·​der·​weight | \ -ˈwāt How to pronounce underweight (audio) \

Medical Definition of underweight

: weighing less than the normal amount for one's age, height, and build underweight children underweight adults typically have a body mass index of less than 18.5


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