Definition of vector noun from the Oxford Advanced Learner's Dictionary

  1. 1 (mathematics) a quantity that has both size and direction Acceleration and velocity are both vectors. compare scalar See related entries: Energy and physical forces, Mathematical terminology
  2. 2 (biology) an insect, etc. that carries a particular disease from one living thing to another Mosquitoes are the vectors in malaria. See related entries: Ailments and diseases, Being ill
  3. 3(specialist) a course taken by an aircraft
  4. Word Origin mid 19th cent.: from Latin, literally ‘carrier’, from vehere ‘convey’.
See the Oxford Advanced American Dictionary entry: vector