To make a threat against someone; to use threats. / To menace, or be dangerous. / To portend, or give a warning of. / To call into question the validity of (a belief, idea, or viewpoint); to challenge.

(ecology, of a plant or animal) At risk of becoming endangered in the near future. / Feeling insecure or vulnerable.

simple past tense and past participle of threaten

Presenting a threat; menacing; frightening.

present participle of threaten

An act of threatening; a threat.

Third-person singular simple present indicative form of threaten

One who threatens.

Capable of being threatened.

plural of threatening