the midnight sun
noun [ S ] uk/ˌmɪd.naɪt ˈsʌn/ us/ˌmɪd.naɪt ˈsʌn/
（南北极地区夏季可见的）夜半太阳，子夜太阳
the sun when seen in the middle of the night in summer in the arctic or antarctic (= the parts of the world furthest to the north and the south)
英汉双解词典收录81607条英汉双解翻译词条，基本涵盖了全部常用单词的读音、翻译及用法，是英语学习的有利工具。