1. an undercurrent in water
Usage: nautical

1. to support or prop up from below
Usage: technical

Examples

• The swimmer was caught in a dangerous underset near the rocky shore.
• Strong undersets made navigation difficult for the small boats.
• The engineers had to underset the foundation with steel beams.
• Workers will underset the sagging floor with additional supports.
• The bridge was underset with concrete pillars for extra stability.