蔓延 (màn yán): to extend; to spread

The forest fire spread rapidly, fueled by dry, strong winds, and consumed thousands of hectares of woodland.

Once an epidemic spreads through a city, the healthcare system will face enormous pressure.

Upon hearing the news that the company was about to lay off employees, a feeling of unease quickly spread through the office.

This weed is extremely resilient and spread across the entire farmland within just a few weeks.

On social media, discussion about that fake news spread like wildfire, eventually causing public panic.