blow (someone) away v.
1. [1910s+] (orig. US black, also blow) to shoot dead.
2. [1960s+] to defeat decisively.
3. [1960s+] to make intoxicated with a drug or drink.
4. [1970s+] (orig. US teen) to impress, to bowl over, to astound.
5. [1980s] (US black) to defeat verbally.
6. [1980s+] to kill.