In my native language, Kaiyumian, "gapi" is not native so it would be transcribed as "gappi" which sometimes means "gap".
When transcribed as "gapii" or "gappii", it is a type of "contextual-linking-word" that means "place where ground is too hot to place bare feet on" (in short, ancient way of saying "volcanic ground")
In Japanese, it is ガピ which just means "gapi". (no meaning)