sunglasses (n.)youdaoicibaDictYouDict[sunglasses 词源字典]
glasses with darkened lenses to protect one's eyes while observing the sun, also sun-glasses, 1878, from sun (n.) + glasses. In popular (non-astronomy) use from 1916. Earlier sunglass (1804) meant a burning glass.[sunglasses etymology, sunglasses origin, 英语词源]