infantile

[in-fuhn-tahyl, -til]

adjective

1. characteristic of or befitting an infant; babyish; childish.

   infantile behavior.

   Synonyms: weak, immature, puerile
   Antonyms: mature, adult

2. of or relating to infants or infancy.

   infantile diseases.

3. Physical Geography.,  youthful.

infantile

/ ˈɪnfənˌtaɪl, ˌɪnfənˈtɪlɪtɪ /

adjective

1. like a child in action or behaviour; childishly immature; puerile

2. of, relating to, or characteristic of infants or infancy

3. in an early stage of development

Other Word Forms

• infantility noun

Word History and Origins

Origin of infantile¹

From the Latin word infantīlis, dating back to 1690–1700. See infant, -ile

Synonym Study

See childish.

Example Sentences

“There was a lo-fi quality about it. It had something candid that didn’t necessarily have an infantile tone but had a lightness. And we could add lyrics to that music.”

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"We say this defamatory, frankly puerile and infantile behaviour by a grown man in respect of these people was, and is, beyond the pale of what is tolerable in society and therefore characterised as criminal."

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If “democracy” has all along been nothing more than a scam rigged to benefit the powerful, then the solution lies in blatant, shameless and overtly infantile version of one-man rule.

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But lately, more disturbing procedures are on the rise - chasing an unrealistic, hyper-feminine, almost infantile ideal.

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As O’Toole also observes, Trump’s anti-European animus has a potent psychosexual subtext, simultaneously rooted in right-wing American macho posturing and his own infantile sense of narcissistic injury.

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Related Words

• childish 
• sophomoric