There are two different definitions of "polar vector."
In elementary math, the term "polar vector" is used to refer to a representation of a vector as a vector magnitude (length) and angle, which is equivalent to specifying its endpoints in polar coordinates (illustrated above).
In physics, a polar vector is a vector such as the radius vector 
that reverses sign when the coordinate axes are reversed. Polar vectors are the type
of vector usually simply known as "vectors."
In contrast, pseudovectors (also called axial vectors)
do not reverse sign when the coordinate axes are reversed. Examples of polar vectors
include 
,
the velocity vector 
, momentum 
, and force 
. The cross product of two
polar vectors is a pseudovector.
