peta- WORD ORIGIN a combining form used in the names of units of measure equal to one quadrillion (1015) of a given base unit: petabyte.
Origin of peta- origin uncertain Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019 British Dictionary definitions for peta- peta- prefix denoting 10 15petametres Symbol: P Word Origin for peta- C20: so named because it is the SI prefix after tera-; on the model of penta-, the prefix after tetra- 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 peta- in Medicine peta- pref. One quadrillion (1015):petagram. The American Heritage® Stedman’s Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company. peta- in Science peta- A prefix that means: One quadrillion (1015), as in petahertz, one quadrillion hertz. 250 (that is, 1,125,899,906,842,624), which is the power of two closest to a quadrillion, as in petabyte. The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.