The Plural of Hypothesis: Here’s What It Is and How to Use It

Ever get stuck wondering what the plural form of hypothesis is in English? Perfect! This article will tell you just that plus give more facts about the word hypothesis, synonyms like a thesaurus, examples, and the history of the word. You will no doubt be an expert on all things surrounding the word hypothesis by the end of this article.

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What Is The Definition Of Hypothesis

As found in the Meriam Webster Dictionary 

  • An assumption or concession made for the sake of argument
  • an interpretation of a practical situation or condition taken as the ground for action
  • a tentative assumption made in order to draw out and test its logical or empirical consequences
  • the antecedent clause of a conditional statement

As found in the Cambridge Dictionary

  • an idea or explanation for something that is based on known facts but has not yet been proved: several hypotheses for global warming have been suggested.

In “The Origin of Hypothesis” it is phrased as a ‘scientific guess’. In the context of science, a hypothesis is a placeholder for a theory until it is proven by science to be accurate.

A scientific hypothesis sed to explain something occurring in our universe that currently does not fit into our current available scientific theories. Scientific hypotheses also include null hypothesis, working hypothesis, and alternative hypothesis. 

History and Origin of The Word

From the Greek hypotithenai to put under, suppose, from hypo- + tithenai to put. The first use of the word hypothesis can be traced back to 1596. Issac Newton actually rejected the hypothesis, he said “Hypotheses non fingo” which translates to “I Frame no hypotheses”. This was back in 1721 in Issac Newton’s book “Opticks, or A Treatise of the Reflections, Refractions, Inflections, and Colours of Light”

What Is More Than One Hypothesis Called?

The plural form of the hypothesis is hypotheses. This is the only way in the English language to make hypothesis plural. Because of the Greek origin, the rule of making a noun that ends in “is” to change it to “es.”


  • Assumption – Something taken for granted
  • Postulate- suggest or assume the existence, fact, or truth of (something) as a basis for reasoning, discussion, or belief
  • Rationale – Logic for belief, action
  • Previous observations- things that were seen or experienced in the past
  • Supposition – guess, belief
  • Theorem – explanation based on hypothesis and experiments done by experimenters using the scientific method
  • Thesis – belief, assumption to be tested
  • Conjecture – speculation, assumption
  • Conclusion – end
  • Tentative Explanation – clarification; reason
  • Guess – belief, speculation 
  • Interpretation – understanding
  • Premise – hypothesis, argument

What Is The Difference Between Hypothesis and Theory?

Since we now know that a hypothesis is a guess or assumption, how is that different from a theory? The definition of a theory is “a supposition or system of ideas intended to explain something, especially one based on general principles independent of the thing to be explained”. 

Although we might think of a theory as something that has not been 100% proven, its definition in the application of science is something that has been tested as an explanation for things occurring. It is still an explanation that is thought of as true until proven otherwise, the difference here is that a hypothesis is thought to explain something not yet tested and could also be thought of as an unproved theory or suggested explanation.

Follow these examples to see the difference in action:

  • Fact: “The clouds are dark outside.” 
  • Hypothesis: “It might storm today.”
  • Theory: “Rain clouds are dark because of their particulate density. The denser the water droplets are in the cloud the more light will be scattered, which will lead to a darker appearance.”
  • Fact: “Light roast coffee has more caffeine than dark roast coffee”
  • Hypothesis: “I should drink a cup of light roast coffee if I want more caffeine”
  • Theory: “During the roasting process caffeine is slowly burned off, therefore it is true that light roast coffee has more caffeine. You should however choose dark roast if you want more caffeine per cup because although per bean light roast has more caffeine, per gram of coffee dark roast contains more caffeine. This is because you have to consider the percent of weight loss that occurs with roasting a coffee to a dark level, which is higher than the percent of caffeine lost, therefore you have more caffeine per gram in dark roast over light roast, only by a minuscule amount.”

What Is The Difference Between An Idea and Hypothesis?

Since a hypothesis is an idea that can be tested, here are some examples of what is just an idea and can’t be tested followed by a similar idea that can be tested and is a hypothesis.

  • Idea: Biden would be a better president vs Trump – Can not be tested since we have no data. 
  • Hypothesis: Obama did a better job at fixing unemployment vs Bush – can be tested by looking at the data.
  • Idea: I could have been the best disc golfer if I started playing when I was a kid – Impossible to test
  • Hypothesis: Paul McBeth probably hit more circle 2 putts on tour last year than Ricky Wysocki. – Can be proven by looking at the data for all their putts on the PDGA tour last year.

Example Sentences In Context

The following are examples of hypothesis in context:

“We came up with the assumptions and then narrowed them down to one hypothesis for each category.” – Forbes

“The notion of hypothesis testing has recently invaded the practice of entrepreneurship as a tool to construct of new ventures” – Forbes

“There’s not one unifying hypothesis as to why, but there’s probably five to 20 different things that have contributed to it.” – USA Today

“Most thinkers or hypothesists of any degree of sobriety allow, that an hypothesis…is not to be received as probably true because it accounts for all the known phenomena since this is a condition sometimes fulfilled tolerably well by two conflicting hypotheses…while there are probably a thousand more which are equally possible, but which, for want of anything analogous in our experience, our minds are unfitted to conceive” – Underdetermination of Scientific Theory

“The expensive tissue hypothesis was focused on human brains and it was never intended as a one-size-fits-all possible explanation that applied across all mammals. The original paper even said that “the cost of the additional brain tissue could have been met by strategies other than a reduction in gut size.” – National Geographic