ガクガク

がくがく
adverb, onomatopoeia
shaking, trembling
movementonomatopoeia
1. shaking, trembling, wobbling
Describes uncontrollable shaking or trembling, typically of the knees or legs from fear, exhaustion, or cold.
膝(ひざ)がガクガクする。
My knees are shaking.
怖(こわ)くて足(あし)がガクガク震(ふる)えた。
My legs trembled with fear.
マラソンの後(あと)、疲(つか)れて膝(ひざ)がガクガクになった。
After the marathon, I was so tired that my knees were wobbling.

ガクガク is an onomatopoeic word describing involuntary, jerky trembling of joints — especially knees and legs. It implies a coarse, unsteady shaking rather than fine shivering.

Common causes

Common patterns

Similar words

  • ブルブル: shivering (from cold or fear, whole-body trembling)
  • ガタガタ: rattling, chattering (teeth chattering, objects rattling)
  • プルプル: quivering slightly (lighter, sometimes cute nuance)

Related Words

Related: がたがた (rattling, chattering)
Compare: ぶるぶる (shivering)
Compare: ぷるぷる (quivering slightly)

Related Articles

Common Onomatopoeia and Mimetic Words
general
Added 2026.2.10 17:06 · Revised 2026.9.2 13:01
10500/10791_gakugaku