See more synonyms for ultra on Thesaurus.com
  1. an extremist, as in politics, religion, fashion, etc.
  2. (initial capital letter) Military. the British code name for intelligence gathered by decrypting German wireless communications enciphered on the Enigma machine during World War II.

Origin of ultra

independent use of ultra-, or shortening of words prefixed with it


  1. 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).

Origin of ultra-

< Latin ultrā (adv. and preposition) on the far side (of), beyond, derivative of *ult(e)r- located beyond

ne plus ultra

[nee pluhs uhl-truh, ney; Latin ne ploo s oo l-trah]
  1. the highest point; acme.
  2. the most intense degree of a quality or state.

Origin of ne plus ultra

1690–1700; < New Latin, Latin nē plūs ultrā (may you) not (go) further beyond (this point)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for ultra

Contemporary Examples of ultra

Historical Examples of ultra

  • None of the groundcars at Ultra Vires was in operating condition.

    Rebels of the Red Planet

    Charles Louis Fontenay

  • Ultra Vires' radio transmitter and receiver had been dismantled.

    Rebels of the Red Planet

    Charles Louis Fontenay

  • Can't touch him on the ultra, so I'm going onto the macro-bands.


    Edward Elmer Smith

  • The "Secret Orchard" is set in the midst of the ultra modern society.

    The Coast of Chance

    Esther Chamberlain

  • He thought of the ultra radio—where could he get all the materials needed?

    Spacehounds of IPC

    Edward Elmer Smith

British Dictionary definitions for ultra


  1. extreme or immoderate, esp in beliefs or opinions
  1. an extremist

Word Origin for ultra

C19: from Latin: beyond, from ulter distant

ne plus ultra

  1. the extreme or perfect point or state

Word Origin for ne plus ultra

literally: not more beyond (that is, go no further), allegedly a warning to sailors inscribed on the Pillars of Hercules at Gibraltar


  1. beyond or surpassing a specified extent, range, or limitultramicroscopic
  2. 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


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."

ne plus ultra

"utmost limit to which one can go," Latin, literally "no more beyond;" the motto traditionally inscribed on the Pillars of Hercules.

Online Etymology Dictionary, © 2010 Douglas Harper

ultra in Medicine


  1. Beyond; on the other side of:ultraviolet.
  2. 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.