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definitions

ultra-

a prefix occurring originally in loanwords from Latin, with the basic meaning “on the far side of, beyond.” In relation to the base to which it is prefixed, ultra- has the senses “located beyond, on the far side of” (ultramontane; ultraviolet), “carrying to the furthest degree possible, on the fringe of” (ultraleft; ultramodern), “extremely” (ultralight); nouns to which it is added denote, in general, objects, properties, phenomena, etc., that surpass customary norms, or instruments designed to produce or deal with such things (ultramicroscope; ultrasound; ultrastructure).

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Nearby words

  1. ultisol,
  2. ulto.,
  3. ultra,
  4. ultra filtration,
  5. ultra vires,
  6. ultra-distance,
  7. ultrabasic,
  8. ultracentrifuge,
  9. ultraclean,
  10. ultraconservative

Origin of ultra-

< Latin ultrā (adv. and preposition) on the far side (of), beyond, derivative of *ult(e)r- located beyond
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for ultra-

ultra-

prefix

beyond or surpassing a specified extent, range, or limitultramicroscopic
extreme or extremelyultramodern

Word Origin for ultra-

from Latin ultrā beyond; see ultra
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 ultra-

ultra-

prefix meaning "beyond" (ultraviolet) or "extremely" (ultramodern), from Latin ultra- from ultra (adv. and prep.) "beyond, on the further side," from PIE *al- "beyond." In common use from early 19c., it appears to have arisen from French political designations. As its own word, a noun meaning "extremist" of various stripes, it is first recorded 1817, from French ultra, shortening of ultra-royaliste "extreme royalist."

Online Etymology Dictionary, © 2010 Douglas Harper
Medicine definitions for ultra-

ultra-

pref.

Beyond; on the other side of:ultraviolet.
Beyond the range, scope, or limit of:ultrasonic.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.