1. The first and the last: "I am Alpha and Omega, the beginning and the ending, saith the Lord" (Revelation 1:8).
2. The most important part.

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.