Related topics: Shapes, patterns
trap·e·zoid /ˈtræpəzɔɪd/ noun [countableC] technical 1. CF British EnglishBrE a shape with four sides, none of which are parallel 不规则四边形
2. American EnglishAmECF a shape with four sides, only two of which are parallel 梯形
→5 see picture at 见图 shape1