It writes "毒 (du2)", meaning the poisons, drugs or viruses when using as a noun, and cruel or noxious when using as a adj and describing a person or a thing.

I just thought I'd point out that "What mean this word" and " What this word(s) mean?" are grammatically incorrect. You can say "What does this word mean?" or "What do these words mean?" :)

Can't go to the link...