Jamming up refers to a situation where something becomes stuck or congested, resulting in a blockage. The antonyms for jamming up can include words like flow, smoothness, consistency, ease, and unobstructed. These words refer to a state of movement without any impediments, obstacles or hindrances. Smoothness refers to a surface that is even and without bumps or interruptions. Consistency refers to a state of being constant or uniform. Ease refers to a state of being able to accomplish something without difficulty, while unobstructed means free from obstacles. Flow refers to a constant and uninterrupted movement. Therefore, to ensure things do not jam up, it is important to maintain the flow, smoothness, consistency, ease, and unobstructed of the things involved.