口哨儿 kǒushàor whistle Definitions Defs Origin Strokes Stroke Words Sentences Sents 口哨 kǒushào noun whistle whistle sound made by pursing the lips or by putting fingers in the mouth; whistle instrument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.