Literally "golden eggs"
Japanese slang for testicles. Not to be confused for golden pillows which is what Son Goku called his grandfather's testicles (used as pillows) in Dragon Ball. Don't look at me that way...

Japanese slang for balls.

Also the name of a Gintama spin-off where Gintoki (Kintoki) has golden hair, Shinpachi has a buttchin, and Kagura is, well... more mature.

Japanese for gold balls(s). Gold is kin and ball is tama. The word is street slang for testicles.

Testicles,
male reproductive organ

Whats Sakata Gintoki says not to call Gintama because its means testicles, also its the name of an Arc in the anime