a person who contributes to the fulfillment of a need or furtherance of an effort or purpose; "my invaluable assistant"; "they hired additional help to finish the work"
a variable quantity that can be resolved into components
any agent (person or animal or microorganism) that carries and transmits a disease; "mosquitos are vectors of malaria and yellow fever"; "fleas are vectors of the plague"; "aphids are transmitters of plant diseases"; "when medical scientists talk about vectors they are usually talking about insects"
a straight line segment whose length is magnitude and whose orientation in space is direction
a thoroughfare (usually including sidewalks) that is lined with buildings; "they walked the streets of the small town"; "he lives on Nassau Street"
the part of a thoroughfare between the sidewalks; the part of the thoroughfare on which vehicles travel; "be careful crossing the street"
people living or working on the same street; "the whole street protested the absence of street lights"
a situation offering opportunities; "he worked both sides of the street"; "cooperation is a two-way street"
the streets of a city viewed as a depressed environment in which there is poverty and crime and prostitution and dereliction; "she tried to keep her children off the street"
some situation or event that is thought about; "he kept drifting off the topic"; "he had been thinking about the subject for several years"; "it is a matter for the police"
a preliminary election where delegates or nominees are chosen
one of the main flight feathers projecting along the outer edge of a bird's wing
not derived from or reducible to something else; basic; "a primary instinct"
of first rank or importance or value; direct and immediate rather than secondhand; "primary goals"; "a primary effect"; "primary sources"; "a primary interest"