The crossbar is a horizontal bar that connects two vertical posts, usually found in sports such as soccer, football, and basketball. Some of the antonyms for the word crossbar include "nonbar," "plain," and "uneven." The non-bar refers to a structure that is devoid of crossbars or horizontal bars. Plain is something that has no unusual or distinctive features. Uneven is something that lacks symmetry or smoothness, hence not regular or uniform. These antonyms are useful for describing objects or spaces that do not have crossbars or are different from the standard crossbar configuration commonly found in sports fields.