scope
How much something includes or the range it covers.
The scope of something is how much it covers or includes. When your teacher explains the scope of your science project, she's describing how big or complex it should be: will you study all birds or just eagles? The whole solar system or just Mars?
Scope helps you understand boundaries and limits. A book's scope might cover the entire Civil War or focus narrowly on a single battle. When someone says a problem is beyond the scope of what they can handle, they mean it's too big or complicated for their current abilities or authority. A school principal might say that changing state education laws is beyond the scope of her power.
In another meaning, a scope is a viewing instrument that helps you see things better. A telescope lets you see distant stars and planets. A microscope reveals tiny creatures invisible to your naked eye. A periscope allows submarine crews to see above the water's surface. Doctors use different kinds of scopes to look inside the body.
When you scope out a situation, you're carefully examining it to understand what you're dealing with. You might scope out a new playground before deciding where to play, or scope out the competition before a spelling bee begins.