1. a sudden increase in public support, interest, or enthusiasm for something
2. a broad, deep ocean swell caused by a distant storm or earthquake
Usage: nautical

Examples

• There was a groundswell of support for the new environmental policy.
• The candidate benefited from a groundswell of grassroots enthusiasm.
• A groundswell of opposition emerged against the proposed tax increase.
• The movement started small but gained momentum from a groundswell of public interest.
• Sailors noticed the groundswell long before the storm reached shore.
• The groundswell made the ship rock gently despite the calm surface winds.
• A groundswell of criticism followed the company’s announcement.