Variable and Versatile

noun

• Something that is likely to vary; something that is subject to variation.
  • usage: "the weather is one variable to be considered"
• A quantity that can assume any of a set of values.
  • synonyms: variable quantity
• A star that varies noticeably in brightness.
  • synonyms: variable star
• A symbol (like x or y) that is used in mathematical or logical expressions to represent a variable quantity.

adjective

• Liable to or capable of change.
  • usage: "rainfall in the tropics is notoriously variable"; "variable winds"; "variable expenses"
• Marked by diversity or difference.
  • usage: "the varying angles of roof slope"; "nature is infinitely variable"
  • synonyms: varying
• Used of a device) designed so that a property (as e. G. Light) can be varied. (
  • usage: "a variable capacitor"; "variable filters in front of the mercury xenon lights"

• (n.) Those parts of the sea where a steady wind is not expected, especially the parts between the trade-wind belts.
• (n.) That which is variable; that which varies or is subject to change.
• (a.) Liable to vary; too susceptible of change; mutable; fickle; unsteady; inconstant; as, the affections of men are variable; passions are variable.
• (n.) A quantity which may increase or decrease; a quantity which admits of an infinite number of values in the same expression; a variable quantity; as, in the equation x2 - y2 = R2, x and y are variables.
• (a.) Having the capacity of varying or changing; capable of alternation in any manner; changeable; as, variable winds or seasons; a variable quantity.
• (n.) A shifting wind or one that varies in force.

Variable is an element in a model. For example, in the model RS&Pt+1 = a + b Tbill t + et, where RS&Pt+1 is the return on the S&P in month t+1 and Tbill is the Tbill return at month t, both RS&P and Tbill are "variables" because they change through time; i. E., they are not constant.

adjective

• Having great diversity or variety.
  • usage: "his various achievements are impressive"; "his vast and versatile erudition"
  • synonyms: various
• Changeable or inconstant.
  • usage: "versatile moods"
• Competent in many areas and able to turn with ease from one thing to another.
  • usage: "a versatile writer"
• Able to move freely in all directions.
  • usage: "an owl's versatile toe can move backward and forward"; "an insect's versatile antennae can move up and down or laterally"; "a versatile anther of a flower moves freely in the wind"

• (a.) Turning with ease from one thing to another; readily applied to a new task or to various subjects; many-sided; as, versatile genius; a versatile politician.
• (a.) Liable to be turned in opinion; changeable; variable; unsteady; inconstant; as versatile disposition.
• (a.) Capable of being turned round.
• (a.) Capable of turning; freely movable; as, a versatile anther, which is fixed at one point to the filament, and hence is very easily turned around; a versatile toe of a bird.