Synonyms for childish

modified

1. Having qualities of a child

   childlike, immature, babyish, baby, infantile, juvenile, puerile, youthful, primitive, boyish, girlish, adolescent, sophomoric, simple, green, soft, kiddish*; see also naive, simple 1, young 2.

   Antonyms adult, mature*, sophisticated.

2. Silly or stupid

   foolish, puerile, absurd, weak; see silly, stupid 1.

3. Childlike because of senility

   senile, in one's dotage, in one's second childhood; see old 1.

childish and childlike are both applied to persons of any age in referring to characteristics or qualities considered typical of a child, childish suggesting unfavorable qualities such as immaturity, foolishness, petulance, etc. and childlike, the favorable, as innocence, guilelessness, trustfulness, etc.