Hi causalset, and welcome. Thanks for the question as it gives me the opportunity to also learn something in the process. I hope the following information is helpful in your study. In the article by Wikipedia, be sure to click on their bracketed numbers which will take you into deeper explanations.
Strong's - 3480 Nazwraiov Nazoraios nad-zo-rah'-yos
from 3478; TDNT-4:874,625; n pr m
AV-of Nazareth 13, Nazarene 2; 15
1) an inhabitant of Nazareth
2) a title given to Jesus in the NT
3) a name given to Christians by the Jews, # Acts 24:5 "For we have found this man a pestilent fellow, and a mover of sedition among all the Jews throughout the world, and a ringleader of the sect of the Nazarenes:"
The following link of Wikipedia seems to bring forth interesting information. Also look at its contents. http://en.wikipedia.org/wiki/Nazarene_(title)
The traditional view is that this word is derived from the Hebrew word for Nazareth (Nazara) that was used in ancient times. "Nazareth", in turn, may be derived from either na•tsar, נָצַר, meaning "to watch," or fromne•tser, נֵ֫צֶר, meaning branch.
Other suggested roots
na•tsar (נָצַר, n-ts-r), pronounced naw•tsar', meaning "to watch, guard, keep". This word also has a messianic association based on a passage in Jeremiah.