四边形 sìbiānxíng quadrilateral Origin Definitions Defs Strokes Stroke Words Sentences Sents 四 sì numeral four the number four; complex form used for financial purposes is 肆 sì边 邊 biān noun side (geometry) side of a geometric shape; a line segment forming a polygon形 xíng nounaffix shape (bound form) shape; form; pattern; configuration