Nicolaitans = "destruction of people"
1) a sect mentioned in Rev 2:6,Rev 2:15, who were charged with holding the error of Balaam, casting a stumbling block before the church of God by upholding the liberty of eating things sacrificed to idols as well as committing fornication
Part of Speech: noun proper masculine
From G3532; a Nicolaite, that is, adherent of Nicolaus: - Nicolaitane.
These two sites give similar information, with the definition from several dictionaries and statistics on the use of the word.
Perseus Digital Library
University of Chicago's Logion lexicon
Thayer's dictionary plus other information.
From this site's dictionary (in Italian)
Click on the first column to search for that word as a form of the root Νικολαΐτης; click on the second column to search for that grammatical form of the root Νικολαΐτης; click on the third column to search for that word and grammatical form; click on the total to search for the root Νικολαΐτης.