gy·​neco·​mas·​tia ˌgī-nə-kō-ˈma-stē-ə How to pronounce gynecomastia (audio)
: excessive development of the breast in the male

Examples of gynecomastia in a Sentence

Recent Examples on the Web That includes breast reductions for young men with gynecomastia, or overgrowth of breast tissue. Claire Bugos, Verywell Health, 30 June 2023 This may include a breast augmentation, a mastectomy for gynecomastia, a hair transplant, a rhinoplasty, liposuction, facial fillers, or hormone therapy. Mira Miller, Verywell Health, 2 June 2023 Clinical gynecomastia is a hormonal imbalance or elevated levels of estrogen and lowered levels of testosterone. Lara Rosenbaum, Men's Health, 25 Jan. 2023 The former Love Island star, 30, live streamed his gynecomastia surgery — or male breast reduction — on social media, posting the lengthy video to his Instagram on Wednesday. Olivia Jakiel,, 13 Apr. 2022 Part of the issue may be that most people don’t realize how common gynecomastia is. Popular Science, 17 Feb. 2021 Murray is among thousands of plaintiffs who claim that taking Risperdal as children caused them to develop an incurable condition called gynecomastia. Megan Cerullo, CBS News, 17 Jan. 2020 The $8 billion verdict had been the biggest to date among lawsuits by about 13,000 plaintiffs alleging that Risperdal caused a condition called gynecomastia in boys, which involves enlargement of breast tissue. Peter Loftus, WSJ, 17 Jan. 2020 Murray’s lawyers pointed to a 2002 label for the drug, in which Janssen said that risks are rare, categorizing their link to gynecomastia at 1 in 1,000. Teo Armus, Washington Post, 9 Oct. 2019

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'gynecomastia.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


gyneco- + Greek mastós "breast" + -ia entry 1, probably after French gynécomastie or German Gynaecomastie or Gynecomastie — more at mastoid entry 1

First Known Use

1881, in the meaning defined above

Time Traveler
The first known use of gynecomastia was in 1881

Dictionary Entries Near gynecomastia

Cite this Entry

“Gynecomastia.” Dictionary, Merriam-Webster, Accessed 14 Apr. 2024.

Medical Definition


variants or chiefly British gynaecomastia
: excessive development of the breast in the male

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