hypothesis
Americannoun
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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.
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a proposition assumed as a premise in an argument.
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the antecedent of a conditional proposition.
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a mere assumption or guess.
noun
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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
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an assumption used in an argument without its being endorsed; a supposition
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an unproved theory; a conjecture
Usage
What is a hypothesis? In science, a hypothesis is a statement or proposition that attempts to explain phenomena or facts. Hypotheses are often tested to see if they are accurate. Crafting a useful hypothesis is one of the early steps in the scientific method, which is central to every field of scientific experimentation. A useful scientific hypothesis is based on current, accepted scientific knowledge and is testable. Outside of science, the word hypothesis is often used more loosely to mean a guess or prediction.
Synonym Usage
See theory.
Other Word Forms
Etymology
Origin of hypothesis
First recorded in 1590–1600, hypothesis is from the Greek word hypóthesis “basis, supposition”; see hypo-, thesis
Explanation
In science, a hypothesis is an idea or explanation that you then test through study and experimentation. Outside science, a theory or guess can also be called a hypothesis. A hypothesis is something more than a wild guess but less than a well-established theory. In science, a hypothesis needs to go through a lot of testing before it gets labeled a theory. In the non-scientific world, the word is used a lot more loosely. A detective might have a hypothesis about a crime, and a mother might have a hypothesis about who spilled juice on the rug. Anyone who uses the word hypothesis is making a guess.
Vocabulary lists containing hypothesis
The SAT: Language of the Test, List 1
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100 Top "SAT" Words
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Tier 2 Words for the SBAC ELA Items
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The authors are preparing experiments to test an alternative theory that they call the Gastropod Hypothesis.
From Science Daily • Jan. 9, 2024
The Grandmother Hypothesis first originated in a 1957 paper by the ecologist George C. Williams, and as Lacreuse said, is often used to explain the existence of menopause.
From Salon • Dec. 11, 2023
Marcos Pérez-Losada, an associate professor of biostatistics and bioinformatics at the GW Milken Institute School of Public Health, and his team were interested in testing what they call "the Grandmother Hypothesis."
From Science Daily • Sep. 29, 2023
The Medea Hypothesis might be epitomized by the story of photosynthetic life on Earth.
From Salon • Dec. 19, 2022
Hypothesis: If I raised enough money to pay for his treatment, then Fig could stay at home, where he belonged.
From "Sir Fig Newton and the Science of Persistence" by Sonja Thomas
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.