Significant means important, meaningful, or large enough to matter. When something is significant, it makes a real difference and deserves attention.

A significant discovery in science might change how we understand the world. A significant amount of money is enough to actually affect your plans, like deciding whether you can buy something you've been wanting. When a teacher says you've made significant progress in math, she means you've genuinely improved in ways that matter, showing real growth in understanding and skill.

The word helps distinguish between things that truly count and things that barely register. If you score one point higher on a test, that's probably not significant. But if you score twenty points higher, that is significant: it shows real growth. A significant event in history, like the invention of the printing press, changed countless lives.

Sometimes people use the word to describe relationships: a significant other is someone truly important in your life, not just an acquaintance. Scientists also use significant in a technical way to describe results that probably didn't happen by accident.

The opposite is insignificant, meaning too small or unimportant to matter. When you're working hard on something, you want your efforts to be significant: to actually make a difference worth noticing.