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definitions

ambi-

  1. a prefix occurring in loanwords from Latin, meaning “both” (ambiguous) and “around” (ambient); used in the formation of compound words: ambitendency.

Origin of ambi-

< Latin; akin to Greek amphí, Albanian mbë, Old Irish imb, imb-, Welsh, Old Breton am, am- (variant em-), Gaulish amb(i)- (see embassy), Old High German umbi (> German um), Old English ymb(e)-, Sanskrit abhí-tas around. Cf. amphi-
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for ambi

ambi-

combining form
  1. indicating bothambidextrous; ambivalence; ambiversion

Word Origin for ambi-

from Latin: round, on both sides, both, from ambo both; compare amphi-
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 ambi

ambi-

word-forming element meaning "both, on both sides," from Latin ambi- "around, round about," from PIE *ambhi "around" (cf. Greek amphi "round about," Sanskrit abhitah "on both sides," Avestan aibi, Old English ymbe, German um, Gaulish ambi-, Old Irish imb- "round about, about," Old Church Slavonic oba, Lithuanian abu "both"). The PIE root probably is an ablative plural of *ant-bhi "from both sides," from *ant- "front, forehead" (see ante).

Online Etymology Dictionary, © 2010 Douglas Harper
ambi in Medicine

ambi-

pref.
  1. Both:ambilateral.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.