noun🔗Share결정 동굴A nodule of stone having a cavity lined with mineral or crystal matter on the inside wall."Maria cracked open the plain-looking rock and gasped; inside was a beautiful geode sparkling with purple crystals. "마리아는 평범해 보이는 바위를 깨뜨리고 숨을 헐떡였다. 안에는 보라색 결정으로 반짝이는 아름다운 결정 동굴이 있었다.geologymineralmaterialnatureChat with AIVocabulary GamePractice Reading