How did Goku and chichi name goten?

Goku and Chi-Chi named their son Goten by combining elements from both their names. "Go" comes from Goku's name, while "ten" is derived from the character "ten" in Chi-Chi's name. Additionally, the name reflects the happy and playful nature of their son, as "goten" can also mean "heavenly" or "sky" in Japanese, symbolizing their hopes for him.