网站首页 汉语 德语 英语
The sun at an early stage of its formation, before becoming dense enough to sustain nuclear reactions.
1940s; earliest use found in Scientific Monthly. From proto- + sun.
雅致网英汉双解词典包含236457条英汉翻译词条，涵盖了常用英语单词及词组短语的翻译及用法，是英语学习的必备工具。