The word 反对 is formed by combining two individual characters, each contributing its core meaning to create a new, composite concept. The first character, 反 (fǎn), carries the inherent idea of "opposite" or "against". The second character, 对 (duì), fundamentally means "to face" or "to be toward". When joined, they create a conceptual image of "facing against" something, which naturally extends to the meaning of "to oppose" or "to object". This formation follows a common pattern in Chinese where two meaningful components are placed together to logically suggest a more specific, related idea.