Synonyms of hypothesis

hypothesis

noun

hī-ˈpä-thə-səs 

as in theory

an idea that is the starting point for making a case or conducting an investigation

working on the hypothesis that teenagers function better in the late morning, some high schools are starting classes later

Synonyms & Similar Words

• theory
• thesis
• proposition
• premise
• assumption
• suggestion
• guess
• supposition
• impression
• proposal
• inference
• theorem
• hunch
• conjecture
• suspicion
• speculation
• presumption
• notion
• generalization
• concept
• presupposition
• surmise
• concession
• construct
• conception
• guesswork
• abstraction
• feeling
• proffer
• inkling

Antonyms & Near Antonyms

• fact
• knowledge
• assurance
• certainty

Synonym Chooser

How does the noun hypothesis differ from other similar words?

The words law and theory are common synonyms of hypothesis. While all three words mean "a formula derived by inference from scientific data that explains a principle operating in nature," hypothesis implies insufficient evidence to provide more than a tentative explanation.

a hypothesis explaining the extinction of the dinosaurs

When can law be used instead of hypothesis?

The synonyms law and hypothesis are sometimes interchangeable, but law implies a statement of order and relation in nature that has been found to be invariable under the same conditions.

the law of gravitation

In what contexts can theory take the place of hypothesis?

The words theory and hypothesis can be used in similar contexts, but theory implies a greater range of evidence and greater likelihood of truth.

the theory of evolution

Example Sentences

Recent Examples of hypothesis

This turns out to be a parable about the long and winding road that runs from mere hypotheses through lab results and real-world data, and then on to solid truth. — Daniel Engber, The Atlantic, 11 July 2026

Powar explained that these systems are increasingly capable of working independently for extended periods, testing hypotheses, solving problems, and adapting their approach without constant human input. — Christopher McFadden, Interesting Engineering, 10 July 2026

This question surfaces the hidden hypothesis behind the initiative. — Expert Panel®, Forbes.com, 10 July 2026

The researchers’ initial hypothesis was that the squids’ brains were somehow denied energy during development, which limited growth, but that wasn’t the only possible answer. — Jeffrey Kluger, Time, 9 July 2026