treacherous.

1. Likely to betray trust, or dangerous because it gives no reliable support or warning.

2. Providing insecure footing or support, or presenting hidden danger.

Use it for

Words that belong together

• treacherous ally
• treacherous betrayal
• treacherous promise
• treacherous ground
• treacherous weather
• treacherous footing

On the page

Her treacherous ally sold the map before the party reached the pass.

Rain made the stairway treacherous beneath their hurried steps.

Usage notes

The betrayal sense concerns trust; the danger sense describes unstable ground, weather, or conditions. Sense 2: This sense is common for surfaces, routes, weather, and situations that conceal risk.