From BiblePortal Wikipedia

Webster's Dictionary [1]

(1): (v. t.) To dull the edge or point of, by making it thicker; to make blunt.

(2): (v. t.) To repress or weaken, as any appetite, desire, or power of the mind; to impair the force, keenness, or susceptibility, of; as, to blunt the feelings.

(3): (a.) Dull in understanding; slow of discernment; stupid; - opposed to acute.

(4): (n.) A fencer's foil.

(5): (n.) A short needle with a strong point. See Needle.

(6): (n.) Money.

(7): (a.) Having a thick edge or point, as an instrument; dull; not sharp.

(8): (a.) Hard to impress or penetrate.

(9): (a.) Abrupt in address; plain; unceremonious; wanting the forms of civility; rough in manners or speech.

King James Dictionary [2]

Blunt, a. from the root of dull.

1. Having a thick edge or point, as an instrument dull not sharp. 2. Dull in understanding slow of discernment. 3. Abrupt in address plain unceremonious wanting the forms of civility rough in manners or speech. 4. Hard to penetrate. Unusual.

Blunt, To dull the edge or point, by making it thicker.

1. To repress or weaken any appetite, desire or power of the mind to impair the force of any passion which affects the mind, or of any evil or good which affects the body as, to blunt the edge of love, of pain, or of suffering.

Your ceaseless endeavors will be exerted to blunt the stings of pain.

Wilson's Dictionary of Bible Types [3]

 Ecclesiastes 10:10 (b) This figure is used to teach us that our knowledge of the Word of God must be fresh, clear and forceful. We must be quick-witted. We must be alert and well trained in the art of affecting the hearts of others. The work of God is easily accomplished when we have been whetted on the emery wheel of Scriptural truth.