underdeveloped
adjective
un·der·de·vel·oped
ˌən-dər-di-ˈve-ləpt 
1
: not normally or adequately developed
underdeveloped muscles
underdeveloped film
2
: having a relatively low economic level of industrial production and standard of living (as from lack of capital)
underdeveloped nations
Examples of underdeveloped in a Sentence
The baby was born with underdeveloped lungs.
Recent Examples on the Web
The virus will break through his underdeveloped blood-brain barrier and begin attacking his brain matter directly, leading to primary measles encephalitis.
—
Elizabeth Bruenig, The Atlantic, 12 Feb. 2026
Perhaps this focus explains why Hedda’s relationships with the male characters seem underdeveloped.
—Emily McClanathan, Chicago Tribune, 11 Feb. 2026
According to her Instagram post, Phillips was born with an underdeveloped kidney.
—Tracy Brown, Los Angeles Times, 11 Feb. 2026
She was born with underdeveloped kidneys and spent the first days of her life in the NICU on dialysis.
—Jessica Schladebeck, New York Daily News, 11 Feb. 2026
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Elizabeth Bruenig, The Atlantic, 12 Feb. 2026
Perhaps this focus explains why Hedda’s relationships with the male characters seem underdeveloped.
—Emily McClanathan, Chicago Tribune, 11 Feb. 2026
According to her Instagram post, Phillips was born with an underdeveloped kidney.
—Tracy Brown, Los Angeles Times, 11 Feb. 2026
She was born with underdeveloped kidneys and spent the first days of her life in the NICU on dialysis.
—Jessica Schladebeck, New York Daily News, 11 Feb. 2026
See All Example Sentences for underdeveloped
Cite this Entry
“Underdeveloped.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/underdeveloped. Accessed 14 Feb. 2026.
Copy CitationKids Definition
underdeveloped
adjective
un·der·de·vel·oped
ˌən-dər-di-ˈvel-əpt
1
: not developed normally or enough
underdeveloped muscles
2
: having a low level of industrial production and standard of living
the underdeveloped nations
Medical Definition
underdeveloped
adjective
un·der·de·vel·oped
ˌən-dər-di-ˈvel-əpt
: not normally or adequately developed
underdeveloped muscles
underdeveloped lungs
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