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a combining form used in the names of units of measure equal to one trillion of a given base unit:
Computers. a combining form of like function with the value 2 40 (=1,099,511,627,766).
Abbreviation: T.
Origin of tera-
< Greek téras monster. See terato- Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2018.
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British Dictionary definitions for tera-


denoting 1012: terameter
Also tebi-. denoting 240: terabyte
Word Origin
from Greek teras monster
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
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Word Origin and History for tera-

prefix used in forming large units of measure (e.g. terabyte), 1947, from Greek teras (genitive teratos) "marvel, monster."

Online Etymology Dictionary, © 2010 Douglas Harper
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tera- in Medicine

tera- pref.
One trillion (1012): terahertz.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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tera- in Science
  1. A prefix that means:

  2. One trillion (1012), as in terahertz, one trillion hertz.

  3. 240 (that is, 1,099,511,627,776), which is the power of two closest to a trillion, as in terabyte.

The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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