膝ひざが笑わらう

expression, godan verb (-u)

knees about to give way; knees buckling

Idiomatic expression describing a sensation of weakness or trembling in the knees, often from fear, exhaustion, or nervousness. The knees are personified as 'laughing' (笑う) to convey the unsteady, wobbling feeling.

• 緊きん張ちょうで膝ひざが笑わらっていた。

  My knees were shaking from nervousness.

• 長ながい階かい段だんを上のぼった後あと、膝ひざが笑わらって立たっていられなかった。

  After climbing the long stairs, my knees were about to give way and I couldn't stand.