(noun. /TOO-mer/)
by Jihae Lee
What does it mean?
A tumor is an abnormal mass of tissue in the body.
Normally, our bodies control tissue growth by regulating cell division and the death of old or damaged cells. Tumors can form when cells grow and divide uncontrollably or fail to die when they should.
Tumors can be either benign or malignant.
Benign tumors are not cancerous. This means that they may grow larger but do not invade nearby tissues or spread to other parts of the body. They can cause health problems by pressing on nearby organs or nerves.
Malignant tumors are cancerous, meaning they can invade nearby tissues and may spread to other parts of the body. They can damage surrounding tissues and interfere with normal organ functions.
How do I use it in a sentence?
“A doctor biopsied the patient’s tumor.”
“The patient was relieved when the doctor told her the tumor was benign, not malignant.”
Illustration comparing normal tissue, a benign tumor, and a malignant tumor. Normal tissue shows organized layers of cells. The benign tumor forms a localized mass without invading the surrounding tissue. The malignant tumor shows abnormal cells invading the surrounding tissue. Image created with BioRender by the author.
Etymology
The word tumor comes from the Latin word tumor, meaning “swelling” or “the condition of being swollen,” which comes from the Latin verb tumere, meaning “to swell.”
The Proto-Indo-European (PIE) root of the word is *teue-, which means “to swell.” The word thumb also comes from this root.
History of usage
The word tumour appeared in the 15th century in a Middle English translation of Chirurgia Magna (1363), a medical book written by Guy de Chauliac, a medieval French surgeon.
At that time, the word tumour meant “act or action of morbid swelling in a living body part.”
For more examples of how the word tumor has been used throughout history and how its meaning has changed, visit this link: tumour, tumor (Oxford English Dictionary).
Related terms
Neoplasm
Benign
Misconceptions (about word usage)
The words tumor and cancer are sometimes mistakenly used interchangeably. While malignant tumors are cancerous, benign tumors are not. Therefore, finding a tumor does not necessarily mean that a person has cancer.
Fields of study in which this word is commonly used
Cancer biology
Oncology
Pathology
Medicine
Immunology
