underweight

noun
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

underweight

adjective

Definition of underweight (Entry 2 of 2)

: weighing less than the normal or requisite amount

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Synonyms & Antonyms for underweight

Synonyms: Adjective

featherlight, feathery, light, lightweight, weightless

Antonyms: Adjective

heavy, hefty, leaden, overweight, ponderous, weighty

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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

On Tuesday, Snapchat's lead underwriter Morgan Stanley downgraded Snap from equal weight to underweight and cut its price target to $16 from $28. Krishna Thakker, Fortune, "Here’s How Many Billions Evan Spiegel Has Lost Since Snap’s IPO," 12 July 2017

Recent Examples on the Web: Adjective

All were underweight, and Gudami bore shrapnel scars on his head. New York Times, "‘Her Eyes Were Full of Fear.’ Turkey Repatriates Children of ISIS Followers.," 27 July 2019 She is being fed 15 times a day and now weighs around 65 pounds, but Nantarika says Mariam is still a bit underweight. Brigit Katz, Smithsonian, "Friendly Baby Dugong Becomes Conservation Symbol in Thailand," 3 July 2019 Black women in New Jersey are three-and-a-half times more likely to die from pregnancy or birth complications than their white counterparts, and their babies are at a much higher risk of being born underweight or dying before their first birthday. Chloe Angyal, Marie Claire, "Cory Booker Gets Real About Reproductive Justice," 20 June 2019 The exact dose of vacuum energy, the precise mass of our underweight Higgs boson, and other anomalies must have high odds within the subset of habitable universes. Quanta Magazine, "In a Multiverse, What Are the Odds?," 3 Nov. 2014 Alaska had the nation’s lowest rate of babies born dangerously underweight in 2017, but the highest rate of child and teenage deaths, according to the latest installment of the Kids Count report that measures how children and teens are faring. Tegan Hanlon, Anchorage Daily News, "Alaska ranks 45th in the nation for children’s well-being, report says," 18 June 2019 Some of them are expensive coffee-table books that weigh about 6 pounds—that’s the weight of a slightly underweight newborn. Liana Satenstein, Vogue, "Sorry Marie Kondo—I Love Mess!," 12 Feb. 2019 More: The animals were unhealthy, many of them matted and underweight. Deasia Paige, Detroit Free Press, "'Hobby breeder' made 108 animals live in feces in Washtenaw Co. home," 22 June 2018 Authorities said despite the boy being underweight, the rest of the family appeared well-fed. Benjamin Brown, Fox News, "Emaciated teen living in barn was 'within a week of death,' authorities say," 20 July 2018

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.

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First Known Use of underweight

Noun

1596, in the meaning defined above

Adjective

1675, in the meaning defined above

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More Definitions for underweight

underweight

adjective

English Language Learners Definition of underweight

: weighing less than the normal or expected amount : too light

underweight

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

Kids Definition of underweight

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

underweight

adjective
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