a. A quantity, such as velocity, completely specified by a magnitude and a direction.
b. A one-dimensional array.
c. An element of a vector space.
2. An organism, such as a mosquito or tick, that carries disease-causing microorganisms from one host to another.
3. A bacteriophage, plasmid, or other agent that transfers genetic material from one cell to another.
4. A force or influence.
5. A course or direction, as of an airplane.
tr.v. vec·tored, vec·tor·ing, vec·tors
To guide (a pilot or aircraft, for example) by means of radio communication according to vectors.
[Latin, carrier, from vehere, vect-, to carry; see wegh- in the Appendix of Indo-European roots.]
vec·tori·al (vĕk-tôrē-əl) adj.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.