hypothesis

The word “hypothesis” means a proposed explanation for something that can be tested through further study or experiment. In plain terms, an educated guess or proposed explanation, made to be tested.

“Hypothesis” is pronounced heye-PO-thih-sihs ([haɪˈpʰɑθəsɪs] in IPA).

Here is “hypothesis” used in a sentence: “Her hypothesis was that the plants would grow faster under blue light.”

“Hypothesis” is a noun.

The word “hypothesis” comes from Greek. From Greek hypothesis ("a placing under, a basis for argument"), from hypotithēmi ("to put forward, suggest").

“Hypothesis” is a fairly common word in modern English, usually learned at around the C2 level.

A hypothesis is a proposed, testable explanation offered before or during investigation, whereas a scientific theory is a well-substantiated explanation supported by a large body of evidence. A theory is far more established than a hypothesis, which still awaits or is undergoing testing.

A hypothesis is a proposed explanation for why something happens, while a prediction is a specific statement about what should be observed if the hypothesis is correct. The prediction is what you test; the hypothesis is what the test supports or refutes.

The plural of hypothesis is "hypotheses," with the ending pronounced "-eez." This follows the pattern of Greek-derived nouns ending in "-is," which form their plural by changing the ending to "-es."

A hypothesis is a proposed explanation framed specifically so it can be tested through study or experiment, whereas an assumption is something taken to be true without testing. A hypothesis invites investigation; an assumption is simply accepted as a starting point.