[ awr-guh-nuh m ]
/ ˈɔr gə nəm /

noun, plural or·ga·na [awr-guh-nuh] /ˈɔr gə nə/, or·ga·nums.

an organon.
  1. the doubling, or simultaneous singing, of a melody at an interval of either a fourth, a fifth, or an octave.
  2. the second part in such singing.

Origin of organum

From Latin, dating back to 1605–15; see origin at organ Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for organum

British Dictionary definitions for organum

/ (ˈɔːɡənəm) /

noun plural -na (-nə) or -nums

a form of polyphonic music originating in the ninth century, consisting of a plainsong melody with parts added at the fourth and fifth
a variant of organon

Word Origin for organum

C17: via Latin from Greek; see organ
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012