The mathematical term for "mean" is "mean".The popular, or colloquial term for "mean" is "average".
No, the math term ratio doesn't mean multiply.
degrees
There is no statistical term such as "deviation mean".
The N on a map would mean North.
Due north is straight north, or exactly north.
Northeast
north due north east
north due north east
Because of your actions
If you mean "due port" it is a direction in sailing/boating, due port is the nautical term for directly left
The North Pole is due north of the Equator.
hydronephrosis
Due south means straight south. This corresponds to the direction found on a compass and lines of longitude on a map.
It was a term often used before the hyphenated term American-Indian or the term Native American became popular. A red Indian was a North American Native.
Not exactly sure of the wording of your question but if you mean the term for past wages due I think it is retroactive pay. Hope that helped.
Line, if you mean a planet's axis as in earth's north pole and south pole.