crepuscular rayWiktionary 原文英美词源链拉丁语Latin约前 75–公元 3 世纪crepusculum‘twilight’↓ 派生英语Englishcrepuscular ray词源说明From the Latin crepusculum (“twilight”).释义名词noun1A sunbeam seen just after sunset or just before sunrise, caused by a cloud below the horizon and dust particles in the air above the horizon.2A cloud shadow cast on the bright sky.