retardation

Noun

 * 1) The act of retarding or delaying; hindrance.
 * 2)  The distance by which one wave is behind another.
 * 3)  The act of diminishing the rate of speed.
 * 4)  A decrease in the speed of telegraph signalling.
 * 5) The extent to which anything is retarded; the result of any retarding or delay; mental, social, or physical slowness.
 * 6)  Extreme stupidity.
 * 7) That which retards; an obstacle; an obstruction.
 * 8)  Deceleration; reduction in the magnitude of velocity.
 * 9)  A suspension which resolves upwards.
 * 1)  A suspension which resolves upwards.

Derived terms

 * growth retardation
 * mental retardation