An onrush is a sudden, powerful forward movement of something, like a flood of water or a crowd of people. Picture the moment a dam breaks and water comes surging through, or imagine the doors opening at a stadium and thousands of fans streaming in all at once. That forceful, unstoppable surge is an onrush.

The word captures both speed and force. When a river experiences an onrush of floodwater after heavy storms, the water rushes forward with overwhelming power. When a team experiences an onrush of energy in the final minutes of a game, they charge forward with renewed intensity and momentum.

You might read about the onrush of winter bringing freezing temperatures, or an onrush of emotions that someone feels when receiving exciting news. The word always suggests something coming fast and strong, whether it's physical like a wave, or abstract like a feeling or an idea. An onrush doesn't trickle in gradually: it arrives with force and momentum that's hard to stop or ignore.