noun
benign tumor
Medical term for a non-cancerous growth. Often contrasted with 悪性腫瘍 (malignant tumor).
検査の結果、その腫瘍は良性腫瘍だとわかった。
The test results showed that the tumor was benign.
Malignant tumor (cancerous). 良性腫瘍 is non-cancerous and generally less dangerous.
Compound of 良性 (benign) + 腫瘍 (tumor). The exact historical derivation is uncertain; the spelling is conventionally associated with the medical meaning.