to become; to appear like; to look like ~
Expresses that something has taken on the appearance or nature of something else, often with a negative or critical nuance.
じみた is used to say that something has become or looks like something else, usually in a way that is not genuine or is childish, silly, or irritating. It often carries a sense of disapproval or mockery. For example, 子供じみた means 'childish' in a bad way, and 忘れじみた means 'forgetful' (as if forgetting has become a habit). It is an adjectival form that modifies a noun, so it comes directly before the noun it describes, like 彼の子供じみた行動 (his childish behavior). This pattern is more common in written or formal speech, and in everyday conversation you'd often use みたい or らしい instead.