The words that are antonyms for "opens throttle" include "closes," "slows down," "stops," and "idles." These words have opposite meanings to "opens throttle," which means to increase the power or speed of something. When you close the throttle or slow down, you are reducing the power or speed of something. Similarly, stopping or idling means that there is no movement or use of power. Antonyms of "opens throttle" can be used in various contexts, such as in driving, mechanics, or aviation. Understanding antonyms for words is essential in improving vocabulary and communication skills.