blow away

1.  Kill, especially by gunshot or explosion. For example, The unit reported that the whole village was blown away. This usage became particularly widespread in the 1960s, during the Vietnam War. [ Slang; early 1990s]
2.  Overcome easily; defeat decisively. For example, Ann said the test would be easy; she would just blow it away, or Jim was sure his crew could blow away their opponents. [Slang; 1960s] Also see blow off, def. 5.
3.  Impress greatly, overwhelm with surprise, delight, or shock, as in That music really blew me away. [Slang; c. 1970] Also see blow one's mind.

To remove (files and directories) from permanent storage, generally by accident. “He reformatted the wrong partition and blew away last night's netnews.” Oppose nuke.