Terrible — or amazing. Modern Japanese slang for both.
The meaning flipped. Older speakers still hear "dangerous, bad"; younger speakers use it for anything extreme in either direction — a stunning view, an amazing meal, or a genuine disaster. Tone and face do all the work.
Originally underworld slang meaning dangerous or risky, as in likely to get you arrested.
Casual only, and generation-dependent. To someone over 60 it still just means bad, so a compliment can land as an insult.
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