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Synonyms

infantilism

American  
[in-fuhn-tl-iz-uhm, -tahy-liz-, in-fan-tl-iz-uhm] / ˈɪn fən tlˌɪz əm, -taɪˌlɪz-, ɪnˈfæn tlˌɪz əm /

noun

  1. the persistence in an adult of markedly childish anatomical, physiological, or psychological characteristics.

  2. an infantile act, trait, etc., especially in an adult.

  3. a speech disorder characterized by speech and voice patterns that are typical of very young children.


infantilism British  
/ ɪnˈfæntɪˌlɪzəm /

noun

  1. psychol

    1. a condition in which an older child or adult is mentally or physically undeveloped

    2. isolated instances of infantile behaviour in mature persons

  2. childish speech; baby talk

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of infantilism

First recorded in 1890–95; infantile + -ism

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“Someone with her intelligence level, matched with an incredibly juvenile infantilism, when those two things come together well, that’s comedy magic,” Seinfeld says.

From Washington Post • Oct. 16, 2018

Not even Tolkien’s vast philological scholarship, his deep knowledge of mythology, and his world-building skills could impress what Moorcock and company saw as a troublesome infantilism inherent in Tolkien’s work.

From The New Yorker • Dec. 31, 2014

Even my son’s embarrassed by the infantilism of my tastes, but there’s some good stuff out there now.

From The Guardian • Oct. 25, 2014

I can’t understand the appeal of a book based on arrested growth, permanent infantilism; most kids want to grow up, not to be mothered for the rest of their lives.

From Time • May 9, 2012

Rickets, mucous disease, lienteric diarrhoea, infantilism, prolapse of the rectum, and infection with thread-worms are common complications.

From The Nervous Child by Cameron, Hector Charles