a force applied from outside; an external force or outside influence (physical or otherwise)
その橋は外力に耐えるように設計されている。
The bridge is designed to withstand external forces.
地震などの外力で建物が傾いた。
The building tilted due to external forces such as an earthquake.
企業は市場という外力によって経営方針を変えた。
The company changed its management policy due to external forces such as the market.