The word 大脑 is formed by combining two individual characters: 大 (dà), meaning "big" or "large", and 脑 (nǎo), meaning "brain". Literally, it translates to "big brain". This construction works conceptually, not just literally, by specifying and narrowing the meaning of the core character "脑". In this context, "big" is used to distinguish the cerebrum or the forebrain, the most prominent and advanced part of the organ responsible for higher functions, from the broader, more general concept of "brain" that might include the entire organ or other parts like the brainstem. Thus, the combination creates a specific term for the primary seat of intelligence and complex thought.