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(ĭn′fən-tl-ĭz′əm, ĭn-făn′tl-)
1. The existence of juvenile physical or psychological characteristics in an adult, as from failure to develop secondary sexual characteristics.
a. Marked immaturity, as in behavior or character.
b. An infantile act or remark.
3. A condition in which one desires to act or be treated like a baby, sometimes associated with a paraphilia.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


1. (Psychology) psychol
a. a condition in which an older child or adult is mentally or physically undeveloped
b. isolated instances of infantile behaviour in mature persons
2. childish speech; baby talk
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈɪn fən tlˌɪz əm, -taɪˌlɪz-, ɪnˈfæn tlˌɪz əm)

1. the persistence in an adult of markedly childish anatomical, physiological, or psychological characteristics.
2. an infantile act, trait, etc.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


the condition of one who is not a child acting abnormally childlike. — infantility, n.infantilistic, adj.
See also: Psychology
-Ologies & -Isms. Copyright 2008 The Gale Group, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.infantilism - an abnormal condition in which an older child or adult retains infantile characteristics
abnormalcy, abnormality - an abnormal physical condition resulting from defective genes or developmental deficiencies
ateleiosis, ateliosis - a form of infantilism characterized by physical underdevelopment but normal intelligence
2.infantilism - infantile behavior in mature persons
misbehavior, misbehaviour, misdeed - improper or wicked or immoral behavior
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


[ɪnˈfæntɪˌlɪzəm] Ninfantilismo m
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005


n. infantilismo, manifestación de características infantiles en la edad adulta.
Inmadurez extrema.
English-Spanish Medical Dictionary © Farlex 2012
References in periodicals archive ?
Strong Towns is then, perhaps unwittingly, written for a post-liberal moment questioning the atomism, materialism, short-termism, and civic infantilism that is the corrosive logic of our age.
Mystical union in the dark night represents an expansion of the soul resistant to the atrophy of intellect, will, and feeling that Haecker fears he is witnessing in the Third Reich: "The essence of the modern dictatorship is the compounding of one-dimensional, flat thought with violence and terror." The dehumanized soul loses its resistance to racialism's irrational rejection of the Biblical claim that "the Spirit can and does blow where he will" and to the puerile theory that God is bounded by obligation to the Aryan master race: "But infantilism is simply a characteristic of the Third Reich" (98).
Have we left our faith in infantilism? We now have our college degrees and even master's and doctorates but has knowledge of our faith kept up?
Due to excess androgens there may be precocious puberty or failure of puberty to occur (sexual infantilism: absent or delayed puberty); ambiguous genitalia, in some females, such that it can be initially difficult to identify external genitalia as 'male' or 'female'; early pubic hair and rapid growth in childhood; excessive facial hair, virilization and/or menstrual irregularity in adolescence; infertility due to anovulation; functional and average sized penis in cases involving extreme virilization (but no sperm), enlarged clitoris and shallow vagina; and pigmentation (due to raised ACTH with lack of cortisol).
What infantilism! American universities need to rise above this nonsense.
It is they who immorally explain away his racism, infantilism, and mean-spirited politics and even his attacks on them.
The patient presented with sexual infantilism, lack of breast development, complete absence of axillary and pubic hair, tall stature, and slenderness.
The vocina's phonetic "ohi" in response to being hit very hard by Ciliegia becomes emblematic of the vocina's infantilism rather than its interpellation of the other.
A popular shitpost image has a cute animal (talking animals, cartoons, and infantilism in general play a huge role in meme-making) asking his friend, "Why are you shitposting?" "I shitpost when I am depressed," the other furry creature replies, staring at the computer screen.
It is necessary that all of present-day society be analyzed by semantic methods in order to discover the degree to which it is dominated by false values, by infantilism, regressive tendencies.
Brooke et al (7) reported a novel missense homozygous R96Q mutation (same mutation of our case) in a 17-year-old 46,XX female patient who had presented with primary amenorrhea, sexual infantilism, and a malignant germ cell tumor.