constant

American Heritage® Dictionary of the English Language, Fourth Edition

1. adj. Continually occurring; persistent.
2. adj. Regularly recurring: plagued by constant interruptions.
3. adj. Unchanging in nature, value, or extent; invariable. See Synonyms at continual.
4. adj. Steadfast in purpose, loyalty, or affection; faithful. See Synonyms at faithful.
5. n. Something that is unchanging or invariable.
6. n. A quantity assumed to have a fixed value in a specified mathematical context.
7. n. An experimental or theoretical condition, factor, or quantity that does not vary or that is regarded as invariant in specified circumstances.

Century Dictionary and Cyclopedia

1. Fixed; not varying; unchanging; permanent; immutable; invariable.
2. Specifically In natural history, not subject to variation; not varying in number, form, color, appearance, etc., in the species or group; always present: as, the middle stria is constant, though the lateral ones are often absent; the reniform spot is constant, but the other markings are subject to variation.
3. Continuing for a long or considerable length of time; continual; enduring; lasting in or retaining a state, quality, or attribute; incessant; ceaseless: as, constant change.
4. Regularly recurring; continually renewed or reiterated; continual: persistent: as, the constant ticking of a clock; the constant repetition of a word; constant moans or complaints.
5. Fixed or firm in mind, purpose, or principle; not easily swayed; unshaken; steady; stable; firm or unchanging, as in affection or duty; faithful; true; loyal; trusty.
6. Fixed in belief or determination; insistent; positive.
7. Fixed; stable; solid: opposed to fluid.
8. Strong; steady.
9. Consistent; logical; reasonable.
10. Indisputably true; evident.
11. Synonyms and Steadfast, stable, unchanging, unalterable, invariable, perpetual, continual; resolute, firm, stanch, unshaken, unwavering, determined; persevering, assiduous, unremitting; trusty.
12. n. That which is not subject to change; something that is always the same in state or operation, or that continually occurs or recurs.
13. n. Specifically— In mathematics, a quantity which is assumed to be invariable throughout a given discussion; in the differential calculus, a quantity whose value remains fixed while others vary continuously. Although the constants do not vary by the variation of those quantities that are at first considered as variables, some or all of them may be conceived to vary in a second kind of change, called the variation of constants. A quantity which upon one supposition would remain constant becomes variable by the introduction of another supposition. Thus, taking into account the earth's attraction only, the longitude of the moon's node is constant, but by the attraction of the sun and planets its place is slowly changed. In this case one of the constants is said to vary. In algebra the unknown quantities are considered as variables, the known quantities and coefficients as constants.
14. n. In physics, a numerical quantity, fixed under uniform conditions, expressing the value of one of the physical properties of a certain substance. Thus, the physical constants of ice are the values of its specific gravity, melting-point, coefficient of expansion, index of refraction, electrical conductivity, etc. Similarly, in the case of a physical instrument a constant is a fixed value depending upon its dimensions, etc. Thus, the constant of a tangent galvanometer is the radius of its coil divided by the number of coils into 6.28318+.

Wiktionary

1. adj. Unchanged through time or space; permanent.
2. adj. Consistently recurring over time; persistent.
3. adj. Steady in purpose, action, feeling, etc.
4. n. That which is permanent or invariable.
5. n. algebra A quantity that remains at a fixed value throughout a given discussion.
6. n. sciences Any property of an experiment, determined numerically, that does not change under given circumstances.
7. n. computing An identifier that is bound to an invariant value.

GNU Webster's 1913

1. adj. obsolete Firm; solid; fixed; immovable; -- opposed to fluid.
2. adj. Not liable, or given, to change; permanent; regular; continuous; continually recurring; steadfast; faithful; not fickle. Opposite of changeable and variable.
3. adj. (Math. & Physics) Remaining unchanged or invariable, as a quantity, force, law, etc.
4. adj. obsolete Consistent; logical.
5. n. That which is not subject to change; that which is invariable.
6. n. (Math.) A quantity that does not change its value; -- used in countradistinction to variable.
7. n. (Astron.) A number whose value, when ascertained (as by observation) and substituted in a general mathematical formula expressing an astronomical law, completely determines that law and enables predictions to be made of its effect in particular cases.
8. n. (Physics) A number expressing some property or condition of a substance or of an instrument of precision.
9. n. (Computers) a data structure that does not change during the course of execution of a program. It may be a number, a string, or a more complex data structure; -- contrasted with variable.

WordNet 3.0

1. adj. uninterrupted in time and indefinitely long continuing
2. n. a number representing a quantity assumed to have a fixed value in a specified mathematical context
3. adj. steadfast in purpose or devotion or affection
4. n. a quantity that does not vary
5. adj. unvarying in nature