Pronunciation: (in-sûr'shun),[key] —n. 1. the act of inserting: the insertion of a coin in a vending machine. 2. something inserted: an insertion in the middle of a paragraph. 3. Bot.,Zool. a. the manner or place of attachment, as of an organ.
b. attachment of a part or organ, with special reference to the site or manner of such attachment.
4. lace, embroidery, or the like, to be sewn at each edge between parts of other material.
5. Aerospace.injection (def. 6).