A hypothesis is a testable idea, explanation, or prediction. It is often used in science and research to connect a question with evidence that can support, weaken, or refine the idea.
What makes a hypothesis testable
A testable hypothesis can be checked through observation, data, comparison, or experiment. It should be specific enough that evidence can reasonably count for or against it.
Hypothesis versus guess
A hypothesis is not just a random guess. It is usually based on background knowledge, a research question, prior evidence, or a theory.
If new evidence does not support a hypothesis, that is still useful learning. Research often improves by revising ideas.