The adjective audacious comes from the Latin word audacia and means "daring, boldness, courage," and often gets applied in situations where someone does something pretty unusual, like becoming an astronaut and going to the moon. It can also mean challenging conventions and doing things that most people don't do, such as when Elizabeth Blackwell became the first woman in the United States to become a doctor. Blackwell then inspired Elizabeth Garrett Anderson to become the first female doctor in England. And the rest is history!