When you turn down an invitation, that's a declination. Another kind of declination is when something slopes down, like the declination of a playground slide.

Look at the noun declination and you can see the verb decline, which means "to lessen," "to slope down," and "to refuse." Declination is the process of doing any of these things. In astronomy, it's also the distance between an object and the celestial equator, measured at an angle. The Latin root is declinatio, "a bending away."

Definitions of declination
  1. noun
    a condition inferior to an earlier condition; a gradual falling off from a better state
    synonyms: decline
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    improvement, melioration
    a condition superior to an earlier condition
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    disuse, neglect
    the state of something that has been unused and neglected
    a condition of decline following successes
    something or someone that has suffered ruin or dilapidation
    something that has been omitted
    type of:
    condition, status
    a state at a particular time
  2. noun
    a downward slope or bend
    synonyms: declension, decline, declivity, descent, downslope, fall
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    acclivity, ascent, climb, raise, rise, upgrade
    an upward slope or grade (as in a road)
    the downward slope of a hill
    a steep place (as on a hill)
    type of:
    incline, side, slope
    an elevated geological formation
  3. noun
    a polite refusal of an invitation
    synonyms: regrets
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    type of:
    acknowledgement, acknowledgment
    a statement acknowledging something or someone
    a message refusing to accept something that is offered
  4. noun
    (astronomy) the angular distance of a celestial body north or to the south of the celestial equator; expressed in degrees; used with right ascension to specify positions on the celestial sphere
    synonyms: celestial latitude, dec
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    type of:
    angular distance
    the angular separation between two objects as perceived by an observer
Word Family

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