n 1  :  a quantity that has magnitude and direction and that is usu. represented by part of a straight line with the given direction and with a length representing the magnitude  2  :  an organism (as an insect) that transmits a pathogen from one organism to another <fleas are s of plague>  - compare CARRIER1a    3  :  a sequence of genetic material (as a transposon or the genome of a bacteriophage) that can be used to introduce specific genes into the genome of an organism vec*to*ri*al adj 
, vt, vec*tored  vec*tor*ing   :  to transmit (a pathogen or disease) from one organism to another  :  act as a vector for <a disease ed by flies>  .
 
 
 
Similar sounding terms:  fac·tor 
 
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