Flowponics is a portmanteau of the words flow and hydroponics.
When two words are combined using the words flow and hydroponics. That is how flowponics is defined. It is the same process as gravponics.
The flowponics theory is an opinion on how a flowponics system works.
When discussing flowponics the flowponics theory is used to describe how someone thinks the system operates. That is the basics of flowponics theory.