constant

adj. continuous; firm, steadfast, unmoving; faithful

n. number with a fixed value (Mathematics)

In mathematics and the mathematical sciences, a constant is a fixed, but possibly unspecified, value. This is in contrast to a variable, which is not fixed.
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Noun
1. a quantity that does not vary
(synonym) constant quantity
(hypernym) quantity
(hyponym) parameter, parametric quantity
2. a number representing a quantity assumed to have a fixed value in a specified mathematical context; "the velocity of light is a constant"
(hypernym) number
(hyponym) Avogadro's number, Avogadro number
Adjective
1. persistent in occurrence and unvarying in nature; "maintained a constant temperature"; "a constant beat"; "principles of unvarying validity"; "a steady breeze"
(synonym) changeless, invariant, steady, unvarying
(similar) invariable
2. continually recurring or continuing without interruption; "constant repetition of the exercise"; "constant chatter of monkeys"
(similar) continual
3. steadfast in purpose or devotion or affection; "a man constant in adherence to his ideals"; "a constant lover"; "constant as the northern star"
(antonym) inconstant
(similar) steadfast, staunch, unswerving
(see-also) faithful
(attribute) constancy, stability
4. uninterrupted in time and indefinitely long continuing; "the ceaseless thunder of surf"; "in constant pain"; "night and day we live with the incessant noise of the city"; "the never-ending search for happiness"; "the perpetual struggle to maintain standards in a democracy"; "man's unceasing warfare with drought and isolation"; "unremitting demands of hunger"
(synonym) ceaseless, incessant, never-ending, perpetual, unceasing, unremitting
(similar) continuous, uninterrupted

adj. constant, firm, steadfast; steady, unfailing

adv. invariably, permanently, constantly

adj. constant, permanent, sustained, continual