a prefix meaning “within,” used in the formation of compound words: intramural.
Compare intro-.

Origin of intra-

< Late Latin intrā-, representing Latin intrā (adv. and preposition); akin to interior, inter-
Can be confusedinter- intra-

Definition for intra (2 of 3)

ab intra

[ ahb in-trah; English ab in-truh ]
/ ɑb ˈɪn trɑ; English æb ˈɪn trə /

adverb Latin.

from inside; from within.

Definition for intra (3 of 3)

intra muros

[ in-trah moo-rohs; English in-truh myoo r-ohs ]
/ ˈɪn trɑ ˈmu roʊs; English ˈɪn trə ˈmyʊər oʊs /

adverb Latin.

within the walls, as of a city. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for intra

British Dictionary definitions for intra



within; insideintravenous

Word Origin for intra-

from Latin intrā on the inside, within; see interior
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 intra


word-forming element meaning "within, inside, on the inside," from Latin intra "on the inside, within," related to inter "between," from PIE *en-t(e)ro-, from root *en "in" (see in). Commonly opposed to extra-, but the use of intra as a prefix was rare in classical Latin.

Online Etymology Dictionary, © 2010 Douglas Harper

Medicine definitions for intra



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

Science definitions for intra


A prefix meaning “inside” or “within,” as in intravenous, within a vein.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.