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per-

1.
a prefix meaning “through,” “thoroughly,” “utterly,” “very”:
pervert; pervade; perfect.
2.
Chemistry. a prefix used in the names of inorganic acids and their salts that possess the maximum amount of the element specified in the base word: percarbonic (H 2 C 2 O 5), permanganic (HMnO 4), persulfuric (H 2 S 2 O 8), acids; potassium permanganate (KMnO 4); potassium persulfate (K 2 S 2 O 8).
Origin
< Latin, combining form of per per, and used as an intensive
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Based on the Random House Dictionary, © Random House, Inc. 2014.
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British Dictionary definitions for per-

per-

prefix
1.
through pervade
2.
throughout perennial
3.
away, beyond perfidy
4.
completely, throughly perplex
5.
(intensifier) perfervid
6.
indicating that a chemical compound contains a high proportion of a specified element peroxide, perchloride
7.
indicating that a chemical element is in a higher than usual state of oxidation permanganate, perchlorate
8.
(not in technical usage) a variant of peroxy- persulphuric acid
Word Origin
from Latin per through
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 per-

word-forming element meaning "through, throughout; thoroughly; entirely, utterly," from Latin preposition per (see per (prep.)).

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

per- pref.

  1. Thoroughly; completely; intensely: perfuse.

  2. Containing an element in its highest oxidation state: perchloric acid.

  3. Containing a large or the largest possible proportion of an element: peroxide.

  4. Containing the peroxy group: peracid.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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5
6
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