For years I mused upon the term, "Rheostat".
Then I discovered that it originated in the years before JJThompson discovered the electron. Nobody knew what electricity was (not that anybody has seen an electron today!) and it was assumed to be some form of fluid.
AIUI, the term, "Rheostat" comes from the Greek for stream "Rheos" and for controller, "Statos". hence Stream Controller.
Now it seems that we should refer to pieces of hook-up wire as, "Rheofores"......Stream Guides!