tumor
In modern clinical usage, the word primarily evokes a sense of medical urgency and anxiety, specifically referring to neoplastic growths. It carries a heavy weight because it is often used as a precursor to the word "cancer," though it technically encompasses both benign (harmless) and malignant (cancerous) masses. There is a sharp distinction between the common layperson's use—which focuses on abnormal cell growth—and the classical medical usage. In the latter context, it refers simply to localized swelling or inflammation (edema), stripped of the connotation of malignancy. Compared to "cyst" or "nodule," a tumor implies a more substantial, solid mass of tissue. The emotional tone is typically clinical and serious, rarely used casually unless describing an obvious physical lump.
Countable when referring to a distinct growth or neoplasm ('the surgeon removed two small tumors'). Uncountable when referring to the medical condition of swelling caused by inflammation ('the area exhibited significant tumor and heat').
Meanings
An abnormal mass of tissue that forms when cells grow and divide more than they should or do not die when they should.
"The MRI scan revealed a small benign tumor in the patient's left kidney."
A swelling of a part of the body, caused by inflammation or congestion; one of the four classical signs of inflammation.
"The physician noted significant tumor and redness around the site of the insect bite."