A testable prediction or proposed explanation for an observation, phenomenon, or scientific problem that can be tested through experimentation or observation.

Here's a breakdown of what that means:

* Testable: A hypothesis must be something that can be tested through experiments or observations.

* Prediction: It's a statement about what you expect to happen based on your understanding of the situation.

* Explanation: It attempts to explain why a certain phenomenon occurs.

* Observation or problem: It arises from a question about something you've noticed or a problem you're trying to solve.

Examples:

* Observation: Plants seem to grow better in sunlight.

* Hypothesis: Plants need sunlight to grow.

* Test: Grow plants in different light conditions and measure their growth.

Key points about hypotheses:

* They can be supported or refuted by evidence.

* They are often stated in the form of an "if... then" statement.

* They are not guesses, but educated predictions based on existing knowledge.

Let me know if you'd like more examples or want to explore different aspects of hypotheses!