Definition

1. Adjective:

   • Capable of being changed or adjusted: Describes a device, setting, or condition that can be altered or controlled.
   • Likely to change frequently; not constant or fixed: Describes something that is prone to change, often in an unpredictable way.
   • Marked by diversity or difference: Describes something that exhibits variation or a range of possibilities.

2. Noun:

   • A symbol representing an unknown or changeable quantity: In mathematics and logic, a symbol (e.g., x, y) used to represent a value that can change.
   • A star with changing brightness: In astronomy, a star whose brightness fluctuates noticeably.
   • A factor or element that is subject to change: Something that is likely to vary and can affect an outcome or situation.
   • A quantity that can assume any value from a set: In mathematics and science, a quantity that is not fixed.

Examples of Usage

• Adjective:

  • The laboratory equipment has a variable voltage setting. (The voltage can be adjusted.)
  • The weather in spring is highly variable. (The weather changes frequently.)
  • The artist used a variable palette of colors. (The artist used a diverse range of colors.)

• Noun:

  • In the equation y = 2x + 3, 'x' is the independent variable. ('x' represents a changeable quantity.)
  • Astronomers study a variable in the constellation Cepheus. (They study a star with changing brightness.)
  • Cost is a key variable in our budget planning. (Cost is a factor that can change.)
  • The speed of the car was the dependent variable in the experiment. (Speed was the measured quantity that changed.)

Advanced Usage

• "Variable rate": An interest rate or payment amount that can change over time.
  • They took out a mortgage with a variable rate.
• "Variable cost": A business expense that changes in proportion to production activity.
  • Raw materials are a variable cost for the factory.

Variants and Related Words

• Variability (n): The quality of being subject to variation or change.
  • The variability of the test results made them unreliable.
• Invariable (adj): Never changing; constant.
  • His morning routine was invariable.
• Vary (v): To change or cause to change.
  • Prices vary from store to store.

Synonyms

• Adjective: Changeable, fluctuating, adjustable, inconsistent, diverse.
• Noun: Factor, parameter, element, unknown (in mathematics).

Related Phrases

• "Control variable": In an experiment, a variable that is kept constant to assess the relationship between other variables.
  • Temperature was a control variable in the chemical reaction.
• "Random variable": In statistics, a variable whose values depend on outcomes of a random phenomenon.
  • The outcome of the dice roll is a random variable.

Adjective

1. (used of a device) designed so that a property (as e.g. light) can be varied
   • a variable capacitor
   • variable filters in front of the mercury xenon lights
2. marked by diversity or difference
   • the varying angles of roof slope
   • nature is infinitely variable
3. liable to or capable of change
   • rainfall in the tropics is notoriously variable
   • variable winds
   • variable expenses

Noun

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