noun[mass noun] Medicine
- A syndrome affecting males in which the cells have an extra X chromosome (in addition to the normal XY), characterized by a tall thin physique, small infertile testes, and enlarged breasts.More example sentences
- Risk factors for breast cancer in men suggest a hormonal imbalance, and up to 20 percent of male breast cancer cases have been associated with Klinefelter's syndrome.
- For example, a screening check of Down's Syndrome might pick up the extra X chromosome that occurs in Chris's condition, Klinefelter's syndrome.
- Men born with a genetic disorder called Klinefelter's syndrome often develop gynecomastia, as do males with adrenal tumors and liver disease.
1940s: named after Harry F. Klinefelter (born 1912), American physician.
More definitions of Klinefelter's syndromeDefinition of Klinefelter's syndrome in:
- The US English dictionary