せざるを得えない

expression, i-adjective

cannot avoid doing; have no choice but to do

Formal/literary expression meaning 'cannot help but do' or 'must do'. Attaches to the negative (未然形) form of a verb. Stronger and more formal than ～なければならない.

See also: ざる

• 悪あく天てん候こうのため、登と山ざんを断だん念ねんせざるを得えなかった。

  Due to the bad weather, we had no choice but to give up climbing the mountain.

• 彼かれの誠せい実じつさを認みとめざるを得えない。

  I cannot help but acknowledge his sincerity.