fierce

Exceedingly violent, severe, ferocious, cruel or savage.

A fierce storm battered the coast.

Their fights with other members of their own kind were always preceded by loud and fierce waulings or savage snarling and snapping of teeth […]

Resolute or strenuously active.

We made a fierce attempt to escape.

I feel a fierce loyalty to my kin.

Threatening in appearance or demeanor.

The lion gave a fierce roar.

Excellent, very good.

Q: "How was the party last night?" A: "Fierce!"

Of exceptional quality, exhibiting boldness or chutzpah.

Tyra said to strike a pose and make it fierce.

Extremely; very.

It was fierce cold last night.