1. to say that you will hurt or punish someone if they do not do what you want
2. to be likely to cause harm or damage to something
3. to be likely to happen in an unwanted or unpleasant way

Examples

• The bully threatens younger students in the hallway.
• She threatens to quit if her demands are not met.
• Climate change threatens polar bear habitats.
• The storm threatens to destroy coastal homes.
• Dark clouds threaten rain for the outdoor wedding.
• The disease threatens the entire crop harvest.
• Economic instability threatens job security nationwide.