Collins English-English Dictionary

decline [dɪ'klaɪn]

1. 1. vb to refuse to do or accept (something), esp politely

2. 2. vi. [intr] to grow smaller; diminish

   demand has declined over the years

3. 3. vi. to slope or cause to slope downwards

4. 4. vi. [intr] to deteriorate gradually, as in quality, health, or character

5. 5. vi. [grammar] to state or list the inflections of (a noun, adjective, or pronoun), or (of a noun, adjective, or pronoun) to be inflected for number, case, or gender - Compare conjugate

6. 6. n gradual deterioration or loss

7. 7. n a movement downward or towards something smaller; diminution

8. 8. n a downward slope; declivity

9. 9. n [archaic] any slowly progressive disease, such as tuberculosis

10. 10. n [Etymology] C14: from Old French decliner to inflect, turn away, sink, from Latin declinare to bend away, inflect grammatically