threatening

To make a threat against someone; to use threats.

“He threatened me with a knife.”

To menace, or be dangerous.

“The rocks threatened the ship's survival.”

To portend, or give a warning of.

“The black clouds threatened heavy rain.”

To be close to equaling or surpassing (a record, etc.)

An act of threatening; a threat.

Presenting a threat; menacing; frightening.

“Never turn your back to someone who is displaying threatening behavior.”