The word cross-bars refers to bars that are placed horizontally across a structure for support or as a means of attachment. Some antonyms to the word cross-bars are diagonal, vertical, or inclined bars that are positioned at an angle rather than horizontal. Another antonym for cross-bars is open space, whereby there are no bars or solid structures present. Additionally, single bars or poles can be considered antonyms to cross-bars, as they are not designed to provide support across a span or distance. While cross-bars may be necessary for certain structures, there are various antonyms to this term that can be equally important depending on the context or purpose.