What is the term used to create a mesh with less vertices using shrinkwrap? I used to know this term but I haven't thought about it in over a year, so I completely forgot about what it's called. The term refers to using the shrink-wrap modifier to maker a new mesh over an old one to change the amount of vertices when the old one has too many?
I think you're referring to Retopology. And yes, in Blender the Shrinkwrap modifier is commonly used in combination with other modifiers to perform retopology.