Unaware means not knowing about something or not noticing what's happening around you. When you're unaware of a fact, you simply don't know it yet. When you're unaware of your surroundings, you're not paying attention to what's going on nearby.

Picture a student so focused on reading that she's completely unaware that her classmates have started packing up their backpacks. She doesn't notice the bell rang or that everyone else is heading to lunch. She's absorbed in her book and unaware of everything happening around her.

Sometimes being unaware is harmless: you might be unaware that your favorite author published a new book until a friend tells you. Other times it matters more: a hiker unaware of an approaching storm could get caught in dangerous weather.

The opposite of unaware is aware, meaning you do know or notice something. People often say someone is “blissfully unaware” when not knowing something actually keeps them happier or less worried. If your parents are planning a surprise party for you, they want you to stay unaware until the big moment.