Proficuous is an uncommon adjective that means productive or successful. If you're looking for other words to use in place of proficuous, try these synonyms: fruitful, advantageous, beneficial, efficient, thriving, prosperous, useful, gainful, valuable, thriving, and effective. Each of these words carries a slightly different connotation, but all denote a sense of positive achievement or success. Whether you're writing a business report, a manifesto, or simply need to describe the benefits of a new project to your team, using synonyms for proficuous can help you express your ideas with greater precision and clarity.