脑儿 nǎor brains Origin Definitions Defs Strokes Stroke Words Sentences Sents 脑 腦 nǎo noun brain The brain of a person or animal; the organ in the head that controls thought and movement.儿 兒 r particleaffix [erhua suffix] A suffix attached to a word to form a retroflex ending, often indicating a small size, a sense of familiarity, or turning a word into a noun.