The phrase "significant accomplishment" means that someone has completed something important or impressive. It refers to a noteworthy achievement or success that is meaningful and impactful. Full definition
Recently, a recruiter put a sentence in a Monster job posting asking applicants to include a one - paragraph description of their most significant accomplishment of the past year. (youtern.com)
Read the article in full to find out how to write about significant accomplishments for a resume. (uptowork.com)