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.

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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

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Etymology

Origin of infantilism

First recorded in 1890–95; infantile + -ism

Example Sentences

Others might speculate on this, but only I can truly channel Trump, since only I possess the requisite degree of infantilism:

From Washington Post • Jan. 27, 2021

He’s speaking about how she catches the “physical awkwardness, social infantilism and self-regard” of certain men.

From New York Times • Oct. 18, 2016

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

Then there is infantilism, which is helped by the giving of thyroid extract.

From The Glands Regulating Personality by Berman, Louis, M.D.

Related Words

• ignorance
• imperfection