1) Backflowing 2) Flow 3) Flowing 1) Backflowing 2) Regurgitation 
Backflow is a term in plumbing for an unwanted flow of water in the reverse direction. It can be a serious health risk for the contamination of potable water supplies with foul water. In the most obvious case, a toilet flush cistern and its water supply must be isolated from the toilet bowl. For this reason, building codes mandate a series of meas...
movement of water back to source e.g. contaminated water in a plumbing system.
Means a flow in a direction contrary to the intended normal direction of flow, usually caused by siphoning.
Movement of water (or other liquid) in any direction other than that intended. 
The reversal of the normal flow of a current. ... See: regurgitation. ... (05 Mar 2000) ... 
(bak´flo) reflux or regurgitation (def. 1). pyelovenous backflow drainage from the renal pelvis into the venous system occurring under certain conditions of back pressure.
The flow of liquids through irrigation into the pipes of a potable or drinking water supply from any source which is opposite to the intended direction of flow.
Type: Term Pronunciation: bak′flō Definitions: 1. The reversal of the normal flow of a fluid or current.
movement of water back to source e.g. contaminated water in a plumbing system.
[n] - a flow that returns toward its source
Means a flow in a direction contrary to the intended normal direction of flow.
backflowing noun a flow that returns toward its source