ラーバMeanings1nounlavaGeological term for molten rock; used in scientific and general contexts. The cross-reference to 溶岩 (ようがん) indicates a synonym, but ラーバ is the direct loanword.See also: 溶岩ハワイの火か山ざんからラーバが流ながれ出でている。Lava is flowing from the volcano in Hawaii.