Fierce

1. Exceedingly violent, severe, ferocious or savage.
2. Resolute or strenuously active.
3. Threatening in appearance or demeanor.
4. (slang, Ireland, rural) Excellent, very good.
5. (slang, US) Of exceptional quality, exhibiting boldness or chutzpah.

Synonyms

• (exceedingly violent): incessive
• (threatening in appearance or demeanor): incessive