Comparable means similar enough to be reasonably compared. When two things are comparable, they share enough important qualities that you can measure them against each other or judge them side by side.

If your teacher says your essay is comparable to the work of older students, she means it matches their quality level. When scientists run experiments, they need comparable conditions: testing plant growth with comparable amounts of sunlight, water, and soil so the results mean something.

The word implies a meaningful similarity, not just any random connection. A bicycle and a car are comparable as forms of transportation, but a bicycle and a sandwich are not comparable in any useful way. Two houses might be comparable in size and location, making it possible to judge their relative value.

Notice that comparable doesn't mean identical or equal. Your basketball skills might be comparable to your friend's even though one of you shoots better and the other plays better defense. The key is that you're in the same general range, close enough that comparison makes sense. When things aren't comparable, like trying to compare the speed of a cheetah to the brightness of a star, you're mixing categories that don't match up in any meaningful way.