Back's
来自Big Physics
Safin(讨论 | 贡献)2022年4月29日 (五) 02:59的版本 (建立内容为“Category:etymology == google == [https://www.google.com.hk/search?q=back's+etymology&newwindow=1&hl=en ref] Old English bæc, of Germanic origin; related to…”的新页面)
Old English bæc, of Germanic origin; related to Middle Dutch and Old Norse bak . The adverb use dates from late Middle English and is a shortening of aback.