Sadducees = "the righteous"
1) a religious party at the time of Christ among the Jews, who denied that the oral law was a revelation of God to the Israelites, and who deemed the written law alone to be obligatory on the nation, as the divine authority. They denied the following doctrines:
1a) resurrection of the body
1b) immortality of the soul
1c) existence of spirits and angels
1d) divine predestination, affirmed free will
Part of Speech: noun masculine
Citing in TDNT: 7:35, 992
Probably from G4524; a Sadducaean (that is, Tsadokian), or follower of a certain heretical Israelite: - Sadducee.
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 Σαδδουκαῖος; click on the second column to search for that grammatical form of the root Σαδδουκαῖος; click on the third column to search for that word and grammatical form; click on the total to search for the root Σαδδουκαῖος.