the persistence in an adult of markedly childish anatomical, physiological, or psychological characteristics.
an infantile act, trait, etc., especially in an adult.
a speech disorder characterized by speech and voice patterns that are typical of very young children.
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How to use infantilism in a sentence
He has transferred his repressed infantilism from the lost family circle to the crowd.The Behavior of Crowds | Everett Dean Martin
The significance of "infantile sexual lesions" has also tended to give place to that of "infantilism of sexuality."Studies in the Psychology of Sex, Volume 1 (of 6) | Havelock Ellis
But in mild cases it may result in a simple myxedematous infantilism.Pedagogical Anthropology | Maria Montessori
The chief element in mental infantilism is maldevelopment of the will.Tics and Their Treatment | Henry Meigne
In them some degree of mental infantilism is of invariable occurrence.Tics and Their Treatment | Henry Meigne
British Dictionary definitions for infantilism
a condition in which an older child or adult is mentally or physically undeveloped
isolated instances of infantile behaviour in mature persons
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