noun, noun or participle which takes 'suru'
Colloquial term for a punch thrown with a closed fist, often used in casual or rough contexts.
See also: パンチ
喧嘩でいきなりグーパンを食らった。
I suddenly got punched with a fist in the fight.
彼は怒って壁にグーパンした。
He got angry and punched the wall with his fist.