Someone who is obsessive-compulsive feels a strong, anxious push to repeat certain actions even when those actions are not needed — checking a lock again and again, washing hands over and over, lining things up until they feel right. The worry and the repeating go together. The medical name for the condition is obsessive-compulsive disorder, often shortened to OCD. Though actually, people now use OCD and obsessive-compulsive very loosely, as a joke about liking things tidy. That stretch can make a real, heavy illness sound like a cute habit, and some people find it unkind. In careful talk, keep the word for the real pattern of anxiety plus repeating, not for I like my desk neat.