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1. A condition inferior to an earlier condition; a gradual falling off from a better state; decline
   - decline
    
2. A downward slope or bend
   - descent, declivity, fall, decline, declension, downslope
    
3. (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
   - celestial latitude, dec
    
4. A polite refusal of an invitation
   - regrets

Derived forms: declinations

Type of: acknowledgement, acknowledgment, angular distance, condition, incline, refusal, side, slope, status

Antonym: improvement

Encyclopedia: Declination