1. Having casual sexual relations frequently with different partners; indiscriminate in the choice of sexual partners.
a. Lacking standards of selection; acting without careful judgment; indiscriminate: criticized him for being promiscuous in his friendships.
b. Showing little forethought or critical judgment; casual: the promiscuous use of the word "populism."
3. Consisting of diverse, unrelated parts or individuals; confused: "Throngs promiscuous strew the level green" (Alexander Pope).
4. Biology Having a variety of functions, targets, or hosts; nonselective: promiscuous enzymes; promiscuous drugs; a promiscuous parasite.
[From Latin prōmiscuus, possessed equally : prō-, intensive pref.; see PRO-1 + miscēre, to mix; see meik- in the Appendix of Indo-European roots.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
The American Heritage Dictionary Blog
Check out our blog, updated regularly, for new words and revised definitions, interesting images from the 5th edition, discussions of usage, and more.
American Heritage Dictionary Products
The American Heritage Dictionary, 5th Edition
The American Heritage Dictionary of Idioms
The American Heritage Roget's Thesaurus
Curious George's Dictionary
The American Heritage Children's Dictionary
The American Heritage Dictionary of Indo-European Roots
The American Heritage Student Grammar Dictionary
The American Heritage Desk Dictionary + Thesaurus
The American Heritage Science Dictionary
The American Heritage Dictionary of Business Terms
The American Heritage Student Dictionary
The American Heritage Essential Student Thesaurus