外力

wàilì
  1. external force
  2. pressure from outside

CEDICT

external force; outside pressure or influence

Wiktionary

外來、外部的力量。

重編國語辭典

Entry Composition

1 外 wài
  1. outside
  2. in addition
  3. foreign
  4. external
2 力 lì
  1. power
  2. force
  3. strength
  4. ability
  5. strenuously