The antonyms for the word "right-side-up" are "upside-down," "inverted," "reversed," "up-ended," or "topsy-turvy." These words describe the state of an object or thing that is rotated or turned in an opposite or different direction from its normal position. For instance, a picture frame can be upside-down when it is hung on a wall, or a glass can be inverted when it is accidentally turned upside-down. Similarly, an object can become up-ended when it is flipped over, or it can become reversed when its orientation is changed. In general, the antonyms of right-side-up imply that something is not in its natural or expected position or direction.