“回声”概念、定义、翻译-科学时代

科学时代收录了1160609条科普词条，基本涵盖了常见科普常识及英语词汇的翻译，是科学学习和研究的有利工具。

单词	回声
释义	文学词汇手册回声 echo
随便看	normal gravity normal gravity field normal gravity field normal gravity formula normal gravity formula normal gravity line normal gravity potential normal gravity potential normal growing stock normal growth rate normal growth rate normal head normal height normal height normal helix normal high-water level normal high water level normal high water level (NHWL) normal high water level--normal high water level (NHWL) normal hours of attendance normal house for sale normal image normal impact normal impact normal impedance