**Vec"tor** (?), n. [L., a bearer, carrier. fr. *vehere*, *vectum*, to carry.]

**1.**

Same as Radius vector.

**2.** Math.

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.