三叶形

It was found that fibers of circular cross section produce greater cohesion in webs and slivers than do trilobal fibers.

圆形横截面纤维在条中，比三叶形横截面纤维能产生较大的粘着作用。

"The Bar tracery of the parallel English Decorated style formed netlike patterns Based on the circle, arch, trefoil, and quatrefoil."

平行的英国装饰风格的条窗花格以圆圈、拱形、三叶形四叶形为基础,形成状图案。