changing location rapidly | the relation between things (or parts of things) with respect to their comparative quantity, magnitude, or degree |
a central nervous system stimulant that increases energy and decreases appetite; used to treat narcolepsy and some forms of depression | the relative magnitudes of two quantities (usually expressed as a quotient) |
a rate (usually rapid) at which something happens | |
the ratio of the focal length to the diameter of a (camera) lens system | |
distance travelled per unit time | |