childish

Childish is an adjective with two related but distinct senses. It can describe traits that are literally characteristic of a child, such as playfulness or simplicity. More commonly, however, it denotes immaturity or behavior that is inappropriate for an adult, including pettiness, impulsivity, or a lack of consideration. In everyday usage, the evaluative sense is predominant and often carries a negative connotation.

Etymology: The word derives from Old English cild "child" with the suffix -ish meaning "having the qualities of." It has cognates in other Germanic languages and evolved to cover both neutral descriptions and pejorative judgments of behavior.

Usage notes: Childish behavior is typically contrasted with childlike behavior, which in contemporary English is often neutral or positive (for example, childlike wonder). The phrase "childish pranks" or "childish name-calling" signals disapproval, especially when applied to adults. In formal writing, more precise terms such as immature, puerile, or juvenile may be preferred.

Grammatical forms: The noun form is childishness; the adverb is childishly. Comparative forms such as more childish or less childish are possible, though uncommon. Examples include: "The debate devolved into childish squabbling" and "Her childish laughter lightened the room." Related terms include childlike and immaturity.