The phrase "one's significant role" refers to the important and impactful position or responsibility that someone has in a particular situation or context. Full definition
Given the opportunity, courthouse librarians could play in significant role in assisting local practitioners in using such resources to manage their practices more efficiently. (slaw.ca)
All such developments will play significant role in making green energy as an appealing asset class. (icotokennews.com)
More clients mean more of a marketing budget and a more significant role for you. (ironpaper.com)