[ uhl-truh ]
/ ˈʌl trə /


going beyond what is usual or ordinary; excessive; extreme.


an extremist, as in politics, religion, fashion, etc.
(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

Definition for ultra (2 of 3)


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

Definition for ultra (3 of 3)

ne plus ultra
[ nee pluhs uhl-truh, ney; Latin ne ploo s oo l-trah ]
/ ˈni ˌplʌs ˈʌl trə, ˈneɪ; Latin ˈnɛ ˌplʊs ˈʊl trɑ /


the highest point; acme.
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. 2020

Example sentences from the Web for ultra

British Dictionary definitions for ultra (1 of 3)

/ (ˈʌltrə) /


extreme or immoderate, esp in beliefs or opinions


an extremist

Word Origin for ultra

C19: from Latin: beyond, from ulter distant

British Dictionary definitions for ultra (2 of 3)

ne plus ultra
/ Latin (ˈneɪ ˈplʊs ˈʊltrɑː) /


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

British Dictionary definitions for ultra (3 of 3)



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

Medical definitions for ultra



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.