1. A natural frequency at which a system oscillates freely without external forcing, determined by the system's physical properties such as mass and stiffness.
Usage: technical; physics and engineering; also called natural frequency or resonant frequency

Examples

• The eigenfrequency of a vibrating beam depends on its length, material, and cross-sectional shape.
• Engineers must calculate the eigenfrequency of a bridge to prevent resonance from wind or traffic.
• A tuning fork vibrates at its eigenfrequency, producing a pure musical note.
• The eigenfrequency of a pendulum increases as its length decreases.
• Seismic engineers study the eigenfrequency of buildings to design structures that can withstand earthquakes.
• In mechanical systems, damping reduces the amplitude of oscillation at the eigenfrequency.