半信半疑 is an adjective describing a state of mixed belief and doubt—neither fully convinced nor entirely skeptical. Literally, it combines two parallel structures: 半 (‘half’) + 信 (‘to believe’) and 半 (‘half’) + 疑 (‘to doubt’), forming a rhythmic, balanced idiom that emphasizes internal uncertainty. It reflects psychological hesitation, often triggered by ambiguous evidence, surprising claims, or unreliable sources.

This expression is commonly used in spoken and written Chinese to depict someone’s cautious, ambivalent attitude—especially when hearing rumors, extraordinary news, or unverified advice. It carries a neutral-to-slightly-negative connotation, implying the person lacks sufficient grounds to commit to belief or rejection. While it can describe individuals, it’s rarely used attributively before nouns without modification (e.g., you’d say ‘他半信半疑’ rather than ‘半信半疑的态度’ without adding ‘的’ or restructuring).