An individual who help in fulfilling an aim: Jenny was very musical and wanted to play the piano, so her mother, as a furtherer, bought one for her so she could take lessons and perhaps become a very good pianist!

Informel, non-standard, furthest; relating to something that is the most faraway place or thing: The elderly Mrs. Smith gold her grandson that the shop was the furtherest one from her home and that he should take his car and not walk, which would take a very long time.