Pronounced: jiǒng; léi; shān zhài
Literally: stunning; thunder; fortified mountain village
Means: shocking/stupefying/amazing/appalling (囧 looks like a face); shocking/stunning/amazing/”thundering” (often meant negatively); knock-off/fake/imitation (as in illegal goods made in the mountains outside government control and regulations).
Each of these words are examples of internet slang making its way into popular usage, like in this computer market advertisement on the back of Tianjin taxi that lists all the things the market isn’t (“not appalling, not thundering, not knock-off”):
See more on how to use “thundered” (雷) here.