From Latin: co- "together" , -linearis "belonging to a line,"
Definition: A set of points that lie in a straight line
Move any of the points around with the mouse. The others will move by themselves so they all remain collinear.
Obviously two points are always collinear, since a straight line can always be drawn through two points.
Sometimes it is spelled 'colinear' (with one L).
We say that "point Q is collinear with points P, R and S". Or put another way, "the points P, Q, R and S are collinear".
It's a similar idea to coplanar
Just as collinear points all lie on a straight line, in the three dimensional world,
when a set of points all lie on the same plane, they are called coplanar.
For more see Coplanar points.
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