Vec"tor (?), n. [L., a bearer, carrier. fr. vehere, vectum, to carry.]
Same as Radius vector.
A directed quantity, as a straight line, a force, or a velocity. Vectors are said to be equal when their directions are the same their magnitudes equal. Cf. Scalar.
⇒ In a triangle, either side is the vector sum of the other two sides taken in proper order; the process finding the vector sum of two or more vectors is vector addition (see under Addition).
© Webster 1913.