An Etymological Dictionary of Astronomy and Astrophysics

Any physical quantity which requires a direction to be stated in order to define it completely, for example velocity. Compare with → scalar.

Etymology (EN): From L. vector “one who carries or conveys, carrier,” from p.p. stem of vehere “carry, convey;” cognate with Pers. vâz (in parvâz “flight”); Av. vaz- “to draw, guide; bring; possess; fly; float,” vazaiti “guides, leads”
(cf. Skt. vah- “to carry, drive, convey,” vahati “carries,”
pravaha- “bearing along, carrying,” pravāha- “running water, stream, river;” O.E. wegan “to carry;” O.N. vegr; O.H.G. weg “way,” wegan “to move,” wagan “cart;” M.Du. wagen “wagon;” PIE base *wegh- “to drive”).

Etymology (PE): Bordâr “carrier,” agent noun from bordan “to carry, transport” (Mid.Pers. burdan;
O.Pers./Av. bar- “to bear, carry,” barəθre “to bear (infinitive);” Skt. bharati “he carries;” Gk. pherein “to carry;” L. ferre “to carry;” PIE base *bher- “to carry”).