If you mean a "Pilgramage" then I can answer your question. A pilgramage is a journey a Christian would take like long ago in the Medieval Ages to the Holy Land, or the place where Jesus died. They considered it a way to help get to heaven or something like that.
There is no widely recognized term or concept called "pilmerge." It may be a typo or a term specific to a certain context that is not widely known. If you can provide more context or clarification, I may be able to assist you further.