From BiblePortal Wikipedia

Webster's Dictionary [1]

(1): ( v. t.) To inflect, or rehearse in order the changes of grammatical form of; as, to decline a noun or an adjective.

(2): ( v. i.) To turn or bend aside; to deviate; to stray; to withdraw; as, a line that declines from straightness; conduct that declines from sound morals.

(3): ( v. i.) To turn away; to shun; to refuse; - the opposite of accept or consent; as, he declined, upon principle.

(4): ( v. i.) A falling off; a tendency to a worse state; diminution or decay; deterioration; also, the period when a thing is tending toward extinction or a less perfect state; as, the decline of life; the decline of strength; the decline of virtue and religion.

(5): ( v. i.) A gradual sinking and wasting away of the physical faculties; any wasting disease, esp. pulmonary consumption; as, to die of a decline.

(6): ( v. i.) To bend, or lean downward; to take a downward direction; to bend over or hang down, as from weakness, weariness, despondency, etc.; to condescend.

(7): ( v. i.) To tend or draw towards a close, decay, or extinction; to tend to a less perfect state; to become diminished or impaired; to fail; to sink; to diminish; to lessen; as, the day declines; virtue declines; religion declines; business declines.

(8): ( v. i.) That period of a disorder or paroxysm when the symptoms begin to abate in violence; as, the decline of a fever.

(9): ( v. t.) To run through from first to last; to repeat like a schoolboy declining a noun.

(10): ( v. t.) To bend downward; to bring down; to depress; to cause to bend, or fall.

(11): ( v. t.) To cause to decrease or diminish.

(12): ( v. t.) To put or turn aside; to turn off or away from; to refuse to undertake or comply with; reject; to shun; to avoid; as, to decline an offer; to decline a contest; he declined any participation with them.

King James Dictionary [2]

Decli'Ne, L to lean.

International Standard Bible Encyclopedia [3]

dē̇ - klı̄n ´ (סוּר , ṣur , or שׂוּר , sūr , נטה , nāṭāh ): In the King James Version this word occurs 9 times in its original sense (now obsolete) of "turn aside." the Revised Version (British and American) substitutes "turn aside" in  Exodus 23:2;  Deuteronomy 17:11;  2 Chronicles 34:2;  Job 23:11 . In  Psalm 102:11;  Psalm 109:23 , the lengthening shadows of afternoon are said to "decline," and the Revised Version (British and American) introduces the word in the same general sense in  Judges 19:8;  2 Kings 20:10;  Jeremiah 6:4 . See Afternoon .