Do something boldly and you act with bravery and confidence. Despite your shyness, you made friends on the first day of school by boldly introducing yourself to your classmates.
When someone takes a risk or musters up a lot of courage, they act boldly. Harriet Tubman boldly led enslaved people to safety on the Underground Railroad. Sir Edmund Hillary and Tenzing Norgay boldly scaled Mt. Everest, the first people known to make it to the summit. And you might boldly speak up in defense of a friend who's being bullied. The Old English root is beald, "stout-hearted."