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[hahy-poth-uh-sis, hi-] /haɪˈpɒθ ə sɪs, hɪ-/
noun, plural hypotheses
[hahy-poth-uh-seez, hi-] /haɪˈpɒθ əˌsiz, hɪ-/ (Show IPA)
a proposition, or set of propositions, set forth as an explanation for the occurrence of some specified group of phenomena, either asserted merely as a provisional conjecture to guide investigation (working hypothesis) or accepted as highly probable in the light of established facts.
a proposition assumed as a premise in an argument.
the antecedent of a conditional proposition.
a mere assumption or guess.
1590-1600; < Greek hypóthesis basis, supposition. See hypo-, thesis
Related forms
hypothesist, noun
counterhypothesis, noun, plural counterhypotheses.
subhypothesis, noun, plural subhypotheses.
Can be confused
hypothesis, law, theory (see synonym study at theory)
Synonym Study
1. See theory. Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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British Dictionary definitions for counter hypotheses


noun (pl) -ses (-ˌsiːz)
a suggested explanation for a group of facts or phenomena, either accepted as a basis for further verification (working hypothesis) or accepted as likely to be true Compare theory (sense 5)
an assumption used in an argument without its being endorsed; a supposition
an unproved theory; a conjecture
Derived Forms
hypothesist, noun
Word Origin
C16: from Greek, from hupotithenai to propose, suppose, literally: put under; see hypo-, thesis
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
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Word Origin and History for counter hypotheses
1590s, from M.Fr. hypothese, from L.L. hypothesis, from Gk. hypothesis "base, basis of an argument, supposition," lit. "a placing under," from hypo- "under" (see sub-) + thesis "a placing, proposition" (see thesis). A term in logic; narrower scientific sense is from 1640s.
Online Etymology Dictionary, © 2010 Douglas Harper
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counter hypotheses in Medicine

hypothesis hy·poth·e·sis (hī-pŏth'ĭ-sĭs)
n. pl. hy·poth·e·ses (-sēz')
A tentative explanation that accounts for a set of facts and can be tested by further investigation.

hy'po·thet'i·cal (hī'pə-thět'ĭ-kəl) adj.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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counter hypotheses in Science
Plural hypotheses (hī-pŏth'ĭ-sēz')
A statement that explains or makes generalizations about a set of facts or principles, usually forming a basis for possible experiments to confirm its viability.

Our Living Language  : The words hypothesis, law, and theory refer to different kinds of statements, or sets of statements, that scientists make about natural phenomena. A hypothesis is a proposition that attempts to explain a set of facts in a unified way. It generally forms the basis of experiments designed to establish its plausibility. Simplicity, elegance, and consistency with previously established hypotheses or laws are also major factors in determining the acceptance of a hypothesis. Though a hypothesis can never be proven true (in fact, hypotheses generally leave some facts unexplained), it can sometimes be verified beyond reasonable doubt in the context of a particular theoretical approach. A scientific law is a hypothesis that is assumed to be universally true. A law has good predictive power, allowing a scientist (or engineer) to model a physical system and predict what will happen under various conditions. New hypotheses inconsistent with well-established laws are generally rejected, barring major changes to the approach. An example is the law of conservation of energy, which was firmly established but had to be qualified with the revolutionary advent of quantum mechanics and the uncertainty principle. A theory is a set of statements, including laws and hypotheses, that explains a group of observations or phenomena in terms of those laws and hypotheses. A theory thus accounts for a wider variety of events than a law does. Broad acceptance of a theory comes when it has been tested repeatedly on new data and been used to make accurate predictions. Although a theory generally contains hypotheses that are still open to revision, sometimes it is hard to know where the hypothesis ends and the law or theory begins. Albert Einstein's theory of relativity, for example, consists of statements that were originally considered to be hypotheses (and daring at that). But all the hypotheses of relativity have now achieved the authority of scientific laws, and Einstein's theory has supplanted Newton's laws of motion. In some cases, such as the germ theory of infectious disease, a theory becomes so completely accepted, it stops being referred to as a theory.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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counter hypotheses in Culture
hypothesis [(heye-poth-uh-sis)]

plur. hypotheses (heye-poth-uh-seez)

In science, a statement of a possible explanation for some natural phenomenon. A hypothesis is tested by drawing conclusions from it; if observation and experimentation show a conclusion to be false, the hypothesis must be false. (See scientific method and theory.)

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