Definition of "polytonality" []

• Simultaneous use of two or more tonalities in a musical composition. (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.

• "By the late 1940s, he was already employing modern classical ideas such as polytonality and dissonance, and working in unusual time signatures to create a distinctive jazz sound."
• "Many of Ives "compositions were ground breaking and anticipated 20th century musical techniques such as polytonality, atonality, 12 tone formations, polymetres, and polyrhythms."
• "Beyond rhythm, Dave Brubeck challenged the public's ear with polytonality, or playing in multiple keys simultaneously."