If you are bareheaded, you have no hat, cap, helmet, or other covering on your head. You can stand bareheaded in the rain, or walk bareheaded into a hall. It works as an adjective (a bareheaded rider) and as an adverb (he stood bareheaded). In older manners, a man took his hat off as a sign of respect, so bareheaded could mark politeness — or, in cold weather, hardship. Today it is usually just a clear description. Though actually, it does not mean bald. A person with a full head of hair is still bareheaded if they are not wearing a hat.