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mastectomy

American  
[ma-stek-tuh-mee] / mæˈstɛk tə mi /

noun

Surgery.

plural

mastectomies
  1. the operation of removing all or part of the breast or mamma.


mastectomy British  
/ mæˈstɛktəmɪ /

noun

  1. the surgical removal of a breast

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

mastectomy Scientific  
/ mă-stĕktə-mē /
  1. Surgical removal of all or part of a breast, performed as a treatment for cancer.

  2. ◆ A radical mastectomy includes excision of the underlying pectoral muscles and regional lymph nodes.


mastectomy Cultural  
  1. The surgical removal of a breast.


Other Word Forms

  • postmastectomy adjective

Etymology

Origin of mastectomy

First recorded in 1920–25; mast- + -ectomy

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

A bout of breast cancer ends with a double mastectomy.

From The Wall Street Journal • Apr. 24, 2026

Then, in 2024, Munn revealed she had been diagnosed the previous year with an aggressive form of breast cancer and had undergone multiple surgeries and a double mastectomy.

From The Wall Street Journal • Apr. 6, 2026

Sloan is currently waiting for a mastectomy, which requires the removal or one or both of the breasts as a method of treating or preventing future cancer growths.

From BBC • Feb. 25, 2026

US actor Angelina Jolie revealed her double mastectomy scars in a photo shoot for Time France, in the magazine's first French edition that launched this week.

From Barron's • Dec. 15, 2025

But the surgeon removed only the lump, which he said was well encapsulated and for some reason did not proceed with a radical mastectomy.

From How and When to Be Your Own Doctor by Solomon, Steve