Dictionary.com
Thesaurus.com

peak programme meter

British  

noun

  1. Abbreviation: PPM.   ppm.  an instrument for assessing the maximum levels of an electrical sound signal

"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