noun Music.
a diatonic series of four tones, the first and last separated by a perfect fourth.

1595–1605; < Greek tetráchordos having four strings. See tetra-, chord1

tetrachordal, adjective
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source Link To tetrachord
World English Dictionary
tetrachord (ˈtɛtrəˌkɔːd)
(in musical theory, esp of classical Greece) any of several groups of four notes in descending order, in which the first and last notes form a perfect fourth
[C17: from Greek tetrakhordos four-stringed, from tetra- + khordē a string]

Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
Cite This Source
Encyclopedia Britannica


musical scale of four notes, bounded by the interval of a perfect fourth (an interval the size of two and one-half steps, e.g., c-f). In ancient Greek music the descending tetrachord was the basic unit of analysis, and scale systems (called the Greater Perfect System and the Lesser Perfect System) were formed by joining successive tetrachords. Only the outer notes of each tetrachord were fixed; the position of the inner pitches determined the genus of the tetrachord. The basic form was the diatonic genus (e.g., a-g-f-e); its modifications formed the chromatic (a-f-f-e) and enharmonic (a-f-e+-e, with e+ being a pitch between e and f) genera. The Greek theorist Cleonides (c. 2nd century AD) discusses the tetrachord and its genera.

Learn more about tetrachord with a free trial on Britannica.com.

Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
Cite This Source
Copyright © 2014 Dictionary.com, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature