Deaerated fuel

[enicalyth]

entrained gases and dust removed?

I may be wrong but deaeration is a process to remove entrained gases and dust.
When a liquid is pumped at pressures near its saturated vapour pressure the presence of dust, entrained gases and even cracks in the pump impeller cause voids in the liquid, and bubbles of gas known as cavitation. This reduces the flow, pressure head and pump life.
“Upstream” and “downstream” in a pump refer to pressure head with “up” being the highest and “down” the lowest and does not refer to direction of liquid flow. Use the terms inlet and outlet instead.
One technique where problems are likely is to apply an inducer to the inlet. An ideal inducer is reversible and its purpose is to help develop the necessary pressure head without shocks that can of themselves produce cavitation.
Regenerative pumps are least likely to experience cavitation problems because the liquid enters and exits the pump over several revolutions of the impeller. They can therefore produce a large pressure difference for comparatively small flows but are capable of producing very high pressure heads and need a quick response pressure relief valve. This liquid reflief outflow is likely to "cavitate" and some ingenuity is resorted to in recirculation. Regenerative pumps are ideally reversible and have the inestimable boon of having the pump cavity remain filled when the pump stops.
I hope this helps to explain what the terms mean and place them in the context of aircraft fuel pumps in particular.