1. Unvarying in nature
   "maintained a constant temperature";
   - changeless, invariant, unvarying
    
2. Steadfast in purpose, devotion or affection
   "constant as the northern star"; "a man constant in adherence to his ideals"; "a constant lover"
    
3. Continuing forever, or for an indefinitely long time
   "in constant pain";
   - ceaseless, incessant, never-ending, perpetual, unceasing, unremitting
    
4. Occurring continuously or frequently
   "The constant noise from traffic kept me awake"
    
5. (of a number) having an unchanging value
   "The experiment used a constant temperature throughout the process";
   - fixed

1. A number representing a quantity assumed to have a fixed value in a specified mathematical context
   "the velocity of light is a constant"
    
2. A quantity that does not vary
   "The speed of light in a vacuum is a constant quantity";
   - constant quantity, invariable

Derived forms: constants

See also: constancy, constantness [rare], continuous, determinate, faithful, immutable, invariable, stability, stable, staunch, steadfast, unchangeable, unfailing, unflagging, uninterrupted, unswerving

Type of: number, quantity

Antonym: inconstant

Encyclopedia: Constant, Joseph