Nicolaitan means "a follower of Nicolas." It comes from two Greek words, nikos and laos. Nikos means "conqueror" or "destroyer," and laos means "people." The original Nicolas was a conqueror or destroyer of the people!
Some people believe that the original Nicolas was Nimrod—the original archrebel, who conquered the people and founded a man-made civilization within two centuries after the Flood (Genesis 10:8-12)! While he was alive, Nimrod put himself in the place of God, or as the biblical text puts it, "he was a mighty hunter before the LORD" (verse 9). When he died, his admirers continued to worship him as a divine hero. They called him "Baal," a name found throughout the Old Testament, meaning "master" or "lord."
Nimrod also had other names. One, commonly used throughout Asia Minor, was "Santa" (see Lempriere's Classical Dictionary.) "Santa Claus" is but a shortened form of "Santa Nicholas" or "Saint Nicholas." Many unknowingly honor this Nicholas even in our day by by observing customs associated with December 25. Christmas originally was the Saturnalia or birthday of Nimrod. Of course, these customs handed down from ancient paganism have been renamed and made to appear innocent and good!
Others think that the Nicolas mentioned in Revelation 2 is the man called "Nicolas, a proselyte from Antioch," ordained a deacon early in the church's history in Acts 6:1-6. Writings of the time say he later came to follow Gnostic teachings and became an ascetic, and many followed his new doctrine. For further information on this Nicolas and his affect on the church, please see Nicolaitanism Today.