From BiblePortal Wikipedia

Webster's Dictionary [1]

(1): (a.) Important.

(2): (prep.) Pertaining to; regarding; having relation to; respecting; as regards.

(3): (p. pr. & vb. n.) of Concern

(4): (n.) That in which one is concerned or interested; concern; affair; interest.

(5): (n.) Importance; moment; consequence.

(6): (n.) Concern; participation; interposition.

(7): (n.) Emotion of mind; solicitude; anxiety.

King James Dictionary [2]

Concerning ppr. Pertaining to regarding having relation to.

The Lord hath spoken good concerning Israel.  Numbers 10 .

I have accepted thee concerning this thing.  Genesis 19 .

This word has been considered a preposition, but most improperly concerning, when so called, refers to a verb, sentence or proposition as in the first example, the word applies to the preceding afirmation. The Lord hath spoken good, which speaking good is concerning Israel. Concerning, in this case, refers to the first clause of the sentence.

International Standard Bible Encyclopedia [3]

kon - sûrn´ing  :

The Revised Version (British and American) makes frequent changes, such as "for," "as for," "from," "about," for "concerning"; "concerning" instead of "for," "of," "over," "in," "against," etc. Some of the other changes are, "unto that which is good" for "concerning" ( Romans 16:19 ), "concerning" instead of "because of" ( Jeremiah 23:9 ), for "the miracle of" ( Mark 6:52 ); for "with" ( Mark 10:41 ), for "of the Lord" ( Acts 18:25 ), "concerning Jesus" (diferent text), "by way of disparagement" ( 2 Corinthians 11:21 ), instead of "concerning reproach"; "Why askest thou me concerning that which is good?" ( Matthew 19:17 ) instead of "Why callest thou me good?" (different text; see the Revised Version, margin).