: of or relating to infants or infancy
: suitable to or characteristic of an infant
especially : very immature
infantile humor
infantility noun

Examples of infantile in a Sentence

the infantile humor that teenage boys are justly famous for
Recent Examples on the Web Protected by her creator, Godwin Baxter (Willem Dafoe), Bella is infantile yet hungry to learn more about the world outside (fun fact: Godwin was Mary Shelley's maiden name). Maureen Lee Lenker, EW.com, 3 Sep. 2023 According to their analysis, the position and the degree of digestion of the two baby dinosaurs suggest that they were devoured at different times, indicating that the young tyrannosaur targeted tiny, infantile prey on at least two separate occasions. Sam Walters, Discover Magazine, 4 Jan. 2024 Her gait, once reminiscent of a toddler, begins to steady as Bella’s infantile brain matures. Sonia Rao, Washington Post, 23 Dec. 2023 Jones knows how dangerous infantile spasms like Mora’s can be — her own son experienced seizures as an infant. Eileen Finan, Peoplemag, 3 Dec. 2023 For infantile psychological reasons, everyone wants to view themselves and their ancestors as heroes. Dick Hoyer, BostonGlobe.com, 27 July 2023 When the pandemic hit in 2020, those children were mostly home for their first few years of life, cocooned from viruses that, in general, strengthen their infantile immune systems. Erika Edwards, NBC News, 24 Oct. 2022 Some pieces, like the new passing game, are in infantile stages. Nate Atkins, The Indianapolis Star, 5 June 2023 He had been diagnosed with infantile spasms, optic nerve hypoplasia, encephalomalacia, and global developmental delays. BostonGlobe.com, 19 Oct. 2021 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'infantile.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1696, in the meaning defined at sense 1

Time Traveler
The first known use of infantile was in 1696

Dictionary Entries Near infantile

Cite this Entry

“Infantile.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infantile. Accessed 25 Feb. 2024.

Kids Definition


in·​fan·​tile ˈin-fən-ˌtīl How to pronounce infantile (audio)
: of, relating to, or resembling infants or infancy
also : childish

Medical Definition


: of, relating to, or occurring in infants or infancy
infantile eczema
: suitable to or characteristic of an infant
especially : very immature

More from Merriam-Webster on infantile

Last Updated: - Updated example sentences
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