Hypothetical means imagined or supposed, not real or proven. When something is hypothetical, it exists only as a possibility or thought experiment, not as actual fact.

Scientists use hypothetical scenarios to explore ideas: “What would happen if we could travel faster than light?” Teachers ask hypothetical questions to make students think: “If you were president, what would you do first?” These situations aren't real, but thinking through them helps us understand principles and test our reasoning.

A hypothetical situation lets you explore consequences without risk. If you're deciding whether to try out for the school play, you might consider the hypothetical outcomes: what if you get the lead role versus what if you don't make the cast at all? You're imagining possibilities before they happen.

The word appears often in phrases like “purely hypothetical” or “speaking hypothetically.” When someone says “hypothetically speaking,” they're signaling that what follows is imaginary, not a real plan or confession. If your friend asks, “Hypothetically, what would you do if you found a lost wallet?” they want to know your principles, not to report an actual situation.

Don't confuse hypothetical with theoretical. Theoretical means based on theory rather than practice, while hypothetical means imagined or supposed. A theoretical physicist works with scientific theories; a hypothetical scenario is simply one you've invented to consider.