Also found in: Thesaurus, Medical, Legal, Acronyms, Wikipedia.


(word root) for, forward, outward
Examples of words with the root pro-: prologue, proceed, protract
Abused, Confused, & Misused Words by Mary Embree Copyright © 2007, 2013 by Mary Embree

pro- 1

1. Acting in the place of; substituting for: proform.
2. Supporting; favoring: prorevolutionary.

[Middle English, from Old French, from Latin pro-, prō-, from prō, for; see per in Indo-European roots.]

pro- 2

a. Earlier; before; prior to: procambium.
b. Rudimentary: pronucleus.
2. Anterior; in front of: procephalic.

[Middle English, from Old French, from Greek, from pro, before, in front; see per in Indo-European roots.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


1. in favour of; supporting: pro-Chinese.
2. in favour of; supporting: pro-Chinese.
3. acting as a substitute for: proconsul; pronoun.
[from Latin prō (adv and prep). In compound words borrowed from Latin, prō- indicates: forward, out (project); forward and down (prostrate); away from a place (prodigal); onward in time or space (proceed); extension outwards (propagate); before in time or place (provide, protect); on behalf of (procure); acting as a substitute for (pronominal); and sometimes intensive force (promiscuous)]


before in time or position; anterior; forward: prophase; procephalic; prognathous.
[from Greek pro (prep) before (in time, position, rank, etc)]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014



adv., n., pl. pros. adv.
1. in favor of a proposition, opinion, etc.
2. the argument, position, arguer, or voter for something.
Compare con 1.
[1350–1400; Middle English < Latin prō (preposition) in favor of, for; akin to per-, Greek pró, Skt pra]



adj., n., pl. pros.
[1840–50; by shortening]


or P.R.O.,

public relations officer.


1. a prefix, having anti- as its opposite, used to form adjectives that have the general sense “favoring” the group, interests, course of action, etc., denoted by the headword: pro-choice; pro-American; prowar.
2. a prefix occurring in loanwords from Latin, with the meanings “forward,” forming esp. verbs denoting forward movement or location (proceed; progress), advancement (promote; propose), or bringing into existence (procreate; produce); “before, outside of” (profane); “in place of” (pronoun).
[< Latin prō-, pro-, comb. form representing prō pro1]


a prefix, occurring orig. in loanwords from Greek, with the meanings “before, beforehand, in front of” (prognosis; prophylactic; prothesis), “front part, extremity” (proboscis), “primitive or embryonic form,” “precursor” (prodrug; pronephros; prosimian).
[< Greek, comb. form of pró for, before; see pro1]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


[ˈprəʊ-] prefix (= in favour of) → pro-
pro-democracy → prodémocratie
Collins English/French Electronic Resource. © HarperCollins Publishers 2005


prefpro-, Pro-; pro-Europeanproeuropäisch
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007


[prəʊ] pref (in favour of) → filo...
pro-American → filoamericano/a
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995


(prəu) in favour of: pro-British
Kernerman English Multilingual Dictionary © 2006-2013 K Dictionaries Ltd.
References in classic literature ?
Tom's heartbreak vanished and he joined the pro- cession, not because he would not a thousand times rather go anywhere else, but because an awful, un- accountable fascination drew him on.
He was in old-time iron armor from head to heel, with a helmet on his head the shape of a nail-keg with slits in it; and he had a shield, and a sword, and a pro- digious spear; and his horse had armor on, too, and a steel horn projecting from his forehead, and gorgeous red and green silk trappings that hung down all around him like a bedquilt, nearly to the ground.
The tall soldier, having prepared his rifle, pro- duced a red handkerchief of some kind.