underweight

noun
un·​der·​weight | \ˌən-dər-ˈwāt \

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

Keep scrolling for more

Synonyms & Antonyms for underweight

Synonyms: Adjective

featherlight, feathery, light, lightweight, weightless

Antonyms: Adjective

heavy, hefty, leaden, overweight, ponderous, weighty

Visit the Thesaurus for More 

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

The latest report found that mothers in India were more likely to deliver underweight babies in households that used wood or dung as cooking fuel. Umair Irfan, Vox, "Why India’s air pollution is so horrendous," 31 Oct. 2018 The children ages 2 to 29 were mostly pale and severely underweight, they hadn't bathed for months and the house reeked of human waste. Brian Melley, Fox News, "Prosecutor: Abused kids upbringing like 'Lord of the Flies'," 22 June 2018 As the adoption dragged on, Boyle said Ngoty was severely underweight, with fever, mouth sores and a fungal rash on her scalp. Maria Sacchetti, Washington Post, "She coached her team to the NCAA tournament. Then she quit, for her daughter.," 28 Mar. 2018 At the time, ranchers were required to remove any dead animals and undertake just one additional preventive measure from a menu of options, which could be as basic as not turning out to pasture underweight calves that could be easier targets. New York Times, "Who’s Afraid of the Big Bad Wolf Scientist?," 5 July 2018 His German shepherd Nala was found abandoned and severely underweight in an apartment in Azusa after the residents left. Hillary Davis, latimes.com, "Coming to the rescue: Newport resident’s dog food company starts nonprofit to get homeless dogs veterinary care," 7 July 2018 America Inc is similarly underweight in the rest of Asia, but there is much less fighting talk about South Korea or Japan. The Economist, "America Inc and the rage against Beijing," 28 June 2018 The report relies on data mostly from 2016, the most recent available, on 16 indicators of well-being, from the highest education level attained by their parents to the percentage of underweight infants to how many teens abuse drugs and alcohol. Kate Santich, OrlandoSentinel.com, "Florida's kids see gains in economic well-being, but gaps persist for children of color," 27 June 2018 In this study, people with BMIs between 22 and 23 had the lowest risk for cardiovascular disease events (e.g. heart attacks), and those with BMIs of 18.5 or lower (classified as underweight) had a higher risk of cardiovascular disease. Sarah Jacoby, SELF, "The Science on Weight and Health," 26 June 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.

See More

First Known Use of underweight

Noun

1596, in the meaning defined above

Adjective

1675, in the meaning defined above

Keep scrolling for more

Learn More about underweight

Share underweight

Statistics for underweight

Look-up Popularity

Time Traveler for underweight

The first known use of underweight was in 1596

See more words from the same year

Keep scrolling for more

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 \

Kids Definition of underweight

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

underweight

adjective
un·​der·​weight | \-ˈwāt \

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

More from Merriam-Webster on underweight

See words that rhyme with underweight

Thesaurus: All synonyms and antonyms for underweight

Comments on underweight

What made you want to look up underweight? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

by force of circumstances

Get Word of the Day daily email!

Test Your Vocabulary

Difficult Vocab Quiz

  • the-education-of-achilles-eugne-delacroix
  • Which is a synonym of discomfit?
Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
Word Winder's CrossWinder

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!