The term "upgrader" can refer to someone who improves or enhances something, such as a software developer who upgrades a program. Synonyms for this word include enhancer, improver, updater, modernizer, and renovator. Additionally, an upgrader may improve their own skills and knowledge, so synonyms for this definition might include self-improver, learner, and self-developer. In a more specific context, an upgrader can also refer to someone who upgrades crude oil, so synonyms for this meaning might include refiner, processor, and converter. Accurately describing someone as an upgrader in their line of work can be crucial on resumes, job applications, and cover letters.