Every once in a while you find a real gem on the Internet. I found one this week: Martin's Norwegian Genealogy Dictionary. As the name implies, this web site contains a dictionary of Norwegian words related to genealogy. If you need to read Norwegian records, you will probably find some of these words. Most of the words are not likely to appear in a common dictionary. However, to be able to make a translation you will also need a common dictionary.
If you have Norwegian ancestry, bookmark this site: http://www.geocities.com/Heartland/Estates/5536/eidhalist.html