Definition of "male pattern baldness" []

• A progressive, diffuse loss of scalp hair in men that begins in the twenties or early thirties, depends on the presence of the androgenic hormone testosterone, and is caused by a combination of genetic and hormonal factors. Also called androgenetic alopecia. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.