All The Tropes:Creating New Redirects
You have a trope, and the name seems to be fine, especially if it's an established term. But it's still kind of an obscure name outside of that particular Fandom or the entertainment industry in general, and/or it's hard to spell. So it's not that likely to be easily searched for.
This is a major cause of duplicates of existing tropes being proposed in the Trope Workshop.
So if a rename isn't called for, creating a redirect is the next best thing. This is popularly abbreviated by saying "redirects are free" -- but it should be noted that the ability to create redirects is not a valid argument for or against renaming.
For instructions (and general guidelines) on exactly how to create a redirect, see Help:Redirects.
Compare Needs a Better Title, Needs a Better Description, Needs an Index, and Pages Needing Images.