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definitions

peri-

  1. a prefix meaning “about” or “around” (perimeter, periscope), “enclosing” or “surrounding” (pericardium), and “near” (perigee, perihelion), appearing in loanwords from Greek (peripeteia); on this model, used in the formation of compound words (perimorph).

Origin of peri-

< Greek, prefixal use of perí (adv. and preposition)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for peri-

peri-

prefix
  1. enclosing, encircling, or aroundpericardium; pericarp; perigon
  2. near or adjacentperihelion

Word Origin for peri-

from Greek peri around, near, about
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
Word Origin and History for peri-

word-forming element meaning "around, about, enclosing," from Greek peri (prep.) "around, about, beyond," cognate with Sanskrit pari "around, about, through," Latin per, from PIE *per- (1) "forward, through" (see per).

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

peri-

pref.
  1. Around; about; enclosing:perimysium.
  2. Near:perinatal.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
peri- in Science

peri-

  1. A prefix that means: “around” (as in pericardium,) or “near” (as in perihelion).
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.