Enlightenment is a state of deep understanding or wisdom that comes from learning, thinking, and experiencing the world. When someone reaches enlightenment about a subject, they've moved beyond confusion or ignorance to really grasp what's true. A student struggling with fractions might suddenly experience a moment of enlightenment when the concept finally clicks and makes perfect sense.

In Buddhism and other Eastern philosophies, enlightenment means achieving the highest level of spiritual understanding: freedom from suffering through deep insight into the nature of reality. Buddhist monks might spend decades meditating and studying in pursuit of enlightenment.

The word also refers to a specific historical period. The Enlightenment (with a capital E) was an intellectual movement in Europe during the 1700s when thinkers emphasized reason, science, and individual rights over tradition and authority. Enlightenment philosophers like Voltaire and John Locke questioned old assumptions and helped spark ideas about democracy, freedom of speech, and scientific inquiry that shaped the modern world. Their writings influenced America's Founding Fathers when they created the U.S. Constitution.

The verb form is enlighten: a teacher enlightens students by helping them understand difficult concepts. To be enlightened means to possess wisdom or understanding that others might lack.