aback
/əˈbæk/adverb
1
- archaic towards or situated to the rear〈古〉向后, 位于后方。
2
- Sailing with the sail pressed backwards against the mast by a headwind【航海】逆帆。
短语
take someone aback
- shock or surprise someone使某人震惊 （或吃惊）：
he was taken aback by her directness.
她的直率让他吃惊。
词源
Old English on bæc （see A-2, BACK）. For long written as two words, the term came to be treated as a single word in nautical use.