1. (Animals) any aquatic bird, such as Podiceps cristatus (great crested grebe), of the order Podicipediformes, similar to the divers but with lobate rather than webbed toes and a vestigial tail. [C18: from French grebe, grÃ¨be of unknown]. originrebe. n. Any of various swimming and diving birds of the family Podicipedidae, having a pointed bill and lobed, fleshy membranes along each toe. [French.
Popular Answers. 1  Productivity = Output / Input. Efficiency = Doing things right. 2  Productivity refers to the conversion level of inputs into outputs. A process that can produce more output using less inputs is more proactive. Efficiency in the economic sense mean that things should be done in an economic way considering that resources are scarce.
Economic Definition of variable input. Offline Version: PDF. Term variable input Definition: An input whose quantity can be changed in the time period under consideration. This should be immediately compared and contrasted with fixed input.The most common example of a variable input is labor.A variable input provides the extra inputs that a firm needs to expand short-run production. In contrast, a fixed input, like capital, provides the capacity constraint in production.his should be immediately compared and contrasted with fixed input. The most common example of a variable input is labor. A variable input provides the extra inputs that a firm needs to expand short-run production. In contrast, a fixed input, like capital, provides the capacity constraint in production.