The phrase "not on the job" refers to when someone is not working or performing their duties. Antonyms for this phrase could include "working," "engaged," "active," "productive," "efficient," "effective," "on duty," "attentive," and "on task." When someone is "on the job," they are present, focused, and productive. On the other hand, when someone is "not on the job," they may be distracted, unproductive, or unengaged. Employers strive to have their employees stay on task while they are on the job so that they can maximize productivity, efficiency, and ultimately achieve their business goals.