The term "cater-cornered" refers to something that is diagonally positioned or situated. It is commonly used when describing the arrangement of furniture, buildings, or streets. The antonyms for cater-cornered are straight, parallel, perpendicular, and aligned. If something is straight, it means that it is in a straight line or that it has no curve or bend. If something is parallel, it means that it is located or arranged in straight lines that never cross each other. On the other hand, if something is perpendicular, it means that it is at a right angle or 90-degree angle to something else. Finally, if something is aligned, it means it is arranged or positioned in a straight line.