Synonyms of underweight

underweight

adjective

as in lightweight

having little weight

the long illness left him frail and underweight

Synonyms & Similar Words

• lightweight
• fragile
• weightless
• small
• light
• feathery
• thin
• tiny
• undersized
• puny
• featherlight
• diminutive
• petite
• smallish
• slender
• wee
• little
• slim
• flimsy
• insubstantial
• bantam
• minute
• slight

Antonyms & Near Antonyms

• overweight
• heavy
• large
• leaden
• weighty
• ponderous
• hefty
• considerable
• extensive
• substantial
• handsome
• huge
• great
• big
• massive
• super
• voluminous
• sizable
• oversize
• goodly
• jumbo
• bulky
• cumbersome
• unwieldy
• largish
• hulking
• king-size
• overscale
• whacking

Example Sentences

Recent Examples of underweight

Upon arrival, several of them were in critical condition and others were underweight with digestive issues. — Richard Tribou, The Orlando Sentinel, 16 June 2026

The assistant medical examiner testified that the child was only 19 pounds, which was considered underweight for her age and height. — Ashley Paul, CBS News, 4 June 2026

Bariatric surgery – a procedure for weight loss – appears to alter set point weight, reducing hunger without decreasing energy expenditure and patients rarely become underweight. — Kim Pfotenhauer, The Conversation, 22 May 2026

The compute build for inference has multi-year lead times, the capacity is already spoken for through 2027, and the buyers are still underweight. — Jon Markman, Forbes.com, 14 May 2026