1. What does it mean?
공굿 abbreviates 공식 굿즈, official goods. Fans use it for merchandise associated with the authorized artist, agency, brand, or production. It contrasts with 비공굿, independently made unofficial merchandise.
Also written or said as 공식굿즈, gonggut
2. The nuance
A seller calling something 공굿 is a claim, not proof of authenticity. The abbreviation alone does not establish who made it or whether a resale listing is genuine.
3. Examples
“공굿 공지는 공식 판매처에서 확인했어.”
I checked the official seller's announcement about the merchandise.
“이번 공굿 중에서는 키링이 제일 마음에 들어.”
Of this release's official merch, I like the keyring best.
Sources
References support the meaning and usage. Example sentences are written for NoCapWiki.