petrichoryoudaoicibaDictYouDict[petrichor 词源字典]
"A pleasant smell that frequently accompanies the first rain after a long period of warm, dry weather", 1960s: blend of petro- 'relating to rocks' (the smell is believed to be caused by a liquid mixture of organic compounds which collects in the ground) and ichor.[petrichor etymology, petrichor origin, 英语词源]