Childish

Part of speech: adjective

Pronunciation: /ˈt͡ʃaɪldɪʃ/

Definitions

1. Characteristic of or suitable for a young person; showing immaturity or lack of sophistication in behavior or thinking
2. Pertaining to behaviors, attitudes, or actions typical of youth
3. displaying naivety or a lack of emotional or intellectual maturity in conduct or thoughts

Etymology: Old English had a word "ċildisċ" built directly on "ċild," the ancestor of modern "child," with the suffix "-isċ" attached. That suffix is the same one that gives us "English" and "Danish" in their older forms, and it simply meant "of the kind belonging to" or "pertaining to." So at its root, the word described whatever belonged to a child: a child's habits, a child's size, a child's manner. Over the Middle English period it passed into the language as "childisch," and the meaning slid from neutral description toward criticism. Something that merely belonged to children began to suggest that a grown person was acting like one, which is why the word now carries a faintly reproachful tone. The Old English base "ċild" itself traces back to a Proto-Indo-European ancestor, but the adjective's story in English is essentially the story of how that simple suffix turned a description into a judgement.

Synonyms: immature, juvenile, puerile, foolish, naive

Antonyms: mature, sophisticated, grown-up, adult, wise