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paradoxical

[par-uh-dok-si-kuh l]
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adjective

having the nature of a paradox; self-contradictory.
Medicine/Medical. not being the normal or usual kind: Stimulants are a paradoxical, albeit effective, medication used for certain forms of hyperactivity.
Sometimes par·a·dox·al.

Origin of paradoxical

paradox + -ical
Related formspar·a·dox·i·cal·ly, adverbpar·a·dox·i·cal·ness, par·a·dox·i·cal·i·ty, nounnon·par·a·dox·i·cal, adjectivenon·par·a·dox·i·cal·ly, adverbnon·par·a·dox·i·cal·ness, nounul·tra·par·a·dox·i·cal, adjectiveul·tra·par·a·dox·i·cal·ly, adverbun·par·a·dox·al, adjectiveun·par·a·dox·i·cal, adjectiveun·par·a·dox·i·cal·ly, adverb

paradox

[par-uh-doks]

noun

a statement or proposition that seems self-contradictory or absurd but in reality expresses a possible truth.
a self-contradictory and false proposition.
any person, thing, or situation exhibiting an apparently contradictory nature.
an opinion or statement contrary to commonly accepted opinion.

Origin of paradox

1530–40; < Latin paradoxum < Greek parádoxon, noun use of neuter of parádoxos unbelievable, literally, beyond belief. See para-1, orthodox
Related formspar·a·dox·i·cal, par·a·dox·al, adjectivepar·a·dox·ol·o·gy, noun

Synonyms for paradox

3. puzzle, anomaly, riddle.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for paradoxal

paradox

noun

a seemingly absurd or self-contradictory statement that is or may be truereligious truths are often expressed in paradox
a self-contradictory proposition, such as I always tell lies
a person or thing exhibiting apparently contradictory characteristics
an opinion that conflicts with common belief
Derived Formsparadoxical, adjectiveparadoxically, adverb

Word Origin for paradox

C16: from Late Latin paradoxum, from Greek paradoxos opposed to existing notions, from para- 1 + doxa opinion
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 paradoxal

paradoxical

adj.

1580s, from paradox + -ical. Competing forms were paradoxal (1560s), paradoxial (1620s), but they survive in niches, if at all. Related: Paradoxically.

paradox

n.

1530s, "statement contrary to common belief or expectation," from Middle French paradoxe (14c.) and directly from Latin paradoxum "paradox, statement seemingly absurd yet really true," from Greek paradoxon, noun use of neuter of adjective paradoxos "contrary to expectation, incredible," from para- "contrary to" (see para- (1)) + doxa "opinion," from dokein "to appear, seem, think" (see decent). Meaning "statement that is seemingly self-contradictory yet not illogical or obviously untrue" is from 1560s.

Online Etymology Dictionary, © 2010 Douglas Harper
paradoxal in Medicine

paradox

[păr′ə-dŏks′]

n.

That which is apparently, though not actually, inconsistent with or opposed to the known facts in any case.
Related formspar′a•dox′i•cal adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
paradoxal in Culture

paradox

A statement that seems contradictory or absurd but is actually valid or true. According to one proverbial paradox, we must sometimes be cruel in order to be kind. Another form of paradox is a statement that truly is contradictory and yet follows logically from other statements that do not seem open to objection. If someone says, “I am lying,” for example, and we assume that his statement is true, it must be false. The paradox is that the statement “I am lying” is false if it is true.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.