View synonyms for declination


[ dek-luh-ney-shuhn ]


  1. a bending, sloping, or moving downward.
  2. deterioration; decline.
  3. a swerving or deviating, as from a standard.
  4. a polite refusal.
  5. Astronomy. the angular distance of a heavenly body from the celestial equator, measured on the great circle passing through the celestial pole and the body.
  6. the formal refusal by a nominee of a nomination to public office.


/ ˌdɛklɪˈneɪʃən /


  1. astronomy the angular distance, esp in degrees, of a star, planet, etc, from the celestial equator measured north (positive) or south (negative) along the great circle passing through the celestial poles and the body δ Compareright ascension
  2. a refusal, esp a courteous or formal one


/ dĕk′lə-nāshən /

  1. On the celestial sphere, the position of a celestial object north or south of the celestial equator . Declination is measured in degrees along a great circle drawn through the object being measured and the north and south celestial poles, with positive values north of the celestial equator and negative values south of it, so that the equator itself is 0° and the north and south celestial poles are +90° and −90° declination respectively.

Discover More

Derived Forms

  • ˌdecliˈnational, adjective

Discover More

Other Words From

  • decli·nation·al adjective
  • predec·li·nation noun

Discover More

Word History and Origins

Origin of declination1

1350–1400; Middle English declinacioun < Old French declinacion < Latin dēclīnātiōn- (stem of dēclīnātiō ), equivalent to dēclīnāt ( us ), literally, turned aside (past participle of dēclīnāre; decline, -ate 1 ) + -iōn- -ion

Discover More

Example Sentences

The declination axis is short, and is supported by a massive goose-neck bolted to the upper end of the polar axis.

The declination slide is changed so little that no means for indicating its position are necessary.

Also the Artificiall and generall declination terminative of Nounes and Verbes.

Webb at once proceeded to take full magnetic declination, time and azimuth observations, Laseron recording for him.

Each day, now, Webb took an approximate magnetic dip and declination in the lee of the break-wind.


Discover More

More About Declination

What does declination mean?

In astronomy, the declination of a celestial object (such as a star or planet) is its position in relation to the celestial equator—the imaginary flat surface that extends out from Earth’s equator in all directions.

In astronomy, heavenly bodies like planets and stars are considered in terms of their position in the celestial sphere—the imaginary sphere that extends out infinitely from Earth. (Picture an infinitely huge ball with Earth as its center.) The celestial equator cuts this sphere in half.

Declination involves the measurement of the position of such objects as being north or south of the celestial equator. Those north of the celestial equator are measured in positive degrees, and those south of it are measured in negative degrees. The declination of the north celestial pole is 90° and the declination of the south celestial pole is -90°. For example, during the summer solstice in the Northern Hemisphere, the Sun is at a declination of 23° north.

Declination also has several more general meanings, but none of them are commonly used. In most of these cases, there is another, more common word that can be used in its place.

Declination can mean a bending or sloping downward. Things that slope this way, such as the parts of a plant, can be described with the adjective declinate. Declination can also mean deterioration—the process or an instance of something getting worse. In both of these senses, it can often be replaced with the noun decline. Declination can also refer to deviation, such as from a standard.

A declination can also be a polite refusal, especially in a formal or official situation. In this sense, it is a noun form of the verb decline, meaning to refuse or to turn something down.

In most cases, it’s much more common for people to use words like deterioration, decline, deviation, and refusal than declination.

Where does declination come from?

The first records of the word declination come from the 1300s. It derives from the Latin dēclīnātus, meaning “turned aside.” Both decline and declination ultimately come from the Latin verb dēclīnāre, meaning “to slope” or “to bend away.”

Because space is three-dimensional, it’s often considered in terms of spheres, curves, and slopes, as opposed to straight lines. In astronomy, the declination of an object like a star is kind of like its latitude and longitude. But instead of being measured on the sphere of Earth, it’s measured on the celestial sphere—the imaginary sphere of space.

Did you know ... ?

What are some other forms related to declination?

  • declinational (adjective)
  • predeclination (noun)

What are some synonyms for declination?

What are some words that share a root or word element with declination

What are some words that often get used in discussing declination?

How is declination used in real life?

The term declination is mostly used in astronomy. Its more general senses are rarely used.



Try using declination!

Which of the following words is a synonym of declination?

A. decline
B. deterioration
C. deviation
D. all of the above