order of magnitude
noun [ C usually singular ] uk/ˌɔː.dər əv ˈmæɡ.nɪ.tjuːd/ us/ˌɔːr.dɚ əv ˈmæɡ.nɪ.tuːd/
（尤指数字的）数量级，大小
the approximate size of something, especially a number
The country's debt this year will be of the same order of magnitude as it was last year. 今年该国的债务与去年相比在同一数量级上。
mathematics specialized成指数增加的，以十倍为单位增加的
a level in a system used for measuring something in which each level is ten times larger than the one before
These processor speeds have recently increased by two orders of magnitude (= by a hundred times). 这些处理器的速度最近增加了两个指数单位（一百倍）。