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(word root) not
Examples of words with the root un-: unreliable
Abused, Confused, & Misused Words by Mary Embree Copyright © 2007, 2013 by Mary Embree

un- 1

1. Not: unhappy.
2. Opposite of; contrary to: unrest.

[Middle English, from Old English; see ne in Indo-European roots.]
Usage Note: There are two prefixes spelled un- in English. One has the basic meaning "not" and attaches chiefly to adjectives (unable, unclean, unequal, unripe, unsafe) and participles used as adjectives (unfeeling, unflinching, unfinished, unsaid). Less frequently, it attaches to nouns (unbelief, unconcern, unrest). Sometimes the noun form of an adjective with the un- prefix has the prefix in-, as in inability, inequality, injustice, and instability. A few stems appear with both prefixes with distinctions of meaning. Inhuman means "brutal, monstrous," while unhuman means "not of human form, superhuman." · When used with adjectives, un- often has a sense distinct from that of non-. Non- picks out the set of things that are not in the category denoted by the stem to which it is attached, whereas un- picks out properties unlike those of the typical examples of the category. Thus nonmilitary personnel are those who are not members of the military, whereas someone who is unmilitary is unlike a typical soldier in dress, habits, or attitudes. · The other prefix un- is not related, despite its common origin in Old English. It forms verbs and expresses removal, reversal, or deprivation: undress, unravel, unnerve. This un- is in fact related to the Greek prefix anti-, "against, opposite, in return," which appears in English as the prefix anti-.

un- 2

1. To reverse or undo the result of a specified action: unbind.
a. To deprive of or remove a specified thing: unfrock.
b. To release, free, or remove from: unyoke.
3. Used as an intensive: unloose.

[Middle English, from Old English on-, alteration (influenced by un-, not) of ond-, and-, an-, against, opposing; see ant- 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.


(freely used with adjectives, participles, and their derivative adverbs and nouns: less frequently used with certain other nouns) not; contrary to; opposite of: uncertain; uncomplaining; unemotionally; untidiness; unbelief; unrest; untruth.
[from Old English on-, un-; related to Gothic on-, German un-, Latin in-]


prefix forming verbs and verbal derivatives
1. denoting reversal of an action or state: uncover; untangle.
2. denoting removal from, release, or deprivation: unharness; unman; unthrone.
3. (intensifier): unloose.
[from Old English un-, on-; related to Gothic and-, German ent-, Latin ante]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


or 'un


Dial. one: young uns; He's a bad un.


or U.N.,

United Nations.


a prefix meaning “not,” freely used as an English formative, giving negative or opposite force in adjectives and their derivative adverbs and nouns (unfair; unfairly; unfairness; unfelt; unseen; unfitting; unformed; unheard-of; un-get-at-able), and less freely used in certain other nouns (unrest; unemployment).
[Middle English un-, on-, Old English; c. Dutch on-, German un-; akin to Latin in-, Greek an-,a-. See a-6, an-1, in-3]


a prefix freely used in English to form verbs expressing a reversal of some action or state, or removal, deprivation, release, etc. (unbend; uncork; unfasten; etc.), or to intensify the force of a verb already having such a meaning (unloose).
[Middle English, Old English un-, on-; c. Dutch ont-=, German ent-; akin to Latin ante, Greek anti; compare ante-, anti-]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


pref (before adj, adv) → un-, nicht; (before n) → Un-
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007
References in classic literature ?
There were people, too; brawny men, with long, coarse, un- combed hair that hung down over their faces and made them look like animals.
In the town were some substantial windowless houses of stone scattered among a wilderness of thatched cabins; the streets were mere crooked alleys, and un- paved; troops of dogs and nude children played in the sun and made life and noise; hogs roamed and rooted contentedly about, and one of them lay in a reeking wallow in the middle of the main thoroughfare and suckled her family.