The word 弱智 is formed by directly combining two independent characters, each contributing its core meaning to create a new, unified concept. The first character, 弱 (ruò), means "weak" or "feeble". The second character, 智 (zhì), means "intelligence", "wisdom", or "mental faculty". When placed together, they form a literal and conceptual compound meaning "weak intelligence", semantically merging to describe an intellectual disability or, in derogatory usage, foolishness.