hypothesis

[hahy-poth-uh-sis, hi-]

noun

plural

hypotheses 

1. 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.

2. a proposition assumed as a premise in an argument.

3. the antecedent of a conditional proposition.

4. a mere assumption or guess.

hypothesis

/ haɪˈpɒθɪsɪs /

noun

1. 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

2. an assumption used in an argument without its being endorsed; a supposition

3. an unproved theory; a conjecture

hypothesis

plural

hypotheses 

1. 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.

hypothesis

1. 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.)

Usage

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.

Other Word Forms

• hypothesist noun
• counterhypothesis noun
• subhypothesis noun

Word History and Origins

Origin of hypothesis¹

First recorded in 1590–1600, hypothesis is from the Greek word hypóthesis “basis, supposition”; hypo-, thesis

Word History and Origins

Origin of hypothesis¹

C16: from Greek, from hupotithenai to propose, suppose, literally: put under; see _hypo- , _thesis

Synonym Study

See theory.

Example Sentences

According to the scientist, one hypothesis explaining the mechanism by which green tea affects obesity involves adiponectin, a protein produced by adipocytes that has anti-inflammatory and metabolic regulation functions.

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To be sure, the findings from the study are hypotheses.

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The research adds weight to the so-called "drunken monkey" hypothesis - the idea that the human appetite for alcohol was inherited from our primate ancestors.

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Throughout the series Lily will form hypotheses and test them to see if the facts fit what she originally thought.

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A lab test later confirmed her grandmother's hypothesis: Kimie had measles, likely contracted after a routine visit to the hospital in the Edmonton area a few weeks earlier.

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Related Words

• assumption 
• axiom 
• conclusion 
• conjecture 
• explanation 
• guess 
• inference 
• interpretation 
• premise 
• proposition 
• rationale 
• supposition 
• theorem 
• thesis 

When To Use

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.