So I wanted a word that was simple to say, and could conjure up a vague idea of what this thing would do. Polyfill just kind of came to me, but it fitted my requirements. Poly meaning it could be solved using any number of techniques - it wasn't limited to just being done using JavaScript, and fill would fill the hole in the browser where the technology needed to be. It also didn't imply "old browser" (because we need to polyfill new browser too).

Also for me, the product Polyfilla (spackling in the US) is a paste that can be put in to walls to cover cracks and holes. I really liked that idea of visualising how we're fixing the browser. Once the wall is flat, you can paint as you please or wallpaper to your heart's content.

https://remysharp.com/2010/10/08/what-is-a-polyfill