幼稚 (yòu zhì) is an adjective meaning 'immature' or 'childish', describing behavior, thinking, or attitudes that lack the sophistication, responsibility, or emotional depth expected of an adult. The character 幼 means 'young' or 'juvenile', while 稚 means 'tender', 'undeveloped', or 'naïve'; together they emphasize underdeveloped mental or emotional maturity—not merely young age, but a mismatch between one’s chronological age and behavioral appropriateness.

This word is commonly used in social, educational, or psychological contexts to gently or critically point out unrefined judgment, impulsive reactions, or oversimplified reasoning. It carries a mildly negative or evaluative tone—more disapproving than neutral—and is rarely used literally for actual children (e.g., we wouldn’t call a five-year-old 幼稚 in most contexts; that would be inappropriate). Instead, it highlights when someone older behaves in ways that seem out of step with their maturity level, such as throwing tantrums, refusing constructive feedback, or making decisions based on emotion alone.