Rigor: A word with two different but related meanings in medicine: 1. A chill, usually with shivering, as at the onset of high fever and chills. 2. Rigidity, as in rigor mortis, the rigidity of a body after death. The alternate spelling rigour is chiefly British. From the French, from the Latin rigor, meaning stiffness, from rigere, to be stiff.
-ine is a suffix used in chemistry to denote two kinds of substance. The first is a chemically basic and alkaloidal substance.
-ite. ( 1 sometimes pejorative) Used to form nouns denoting followers or adherents of a specified person, idea, doctrine, movement, etc. Adamsite, Campbellite, Jacobite, laborite, Mansonite, Reaganite, Thatcherite. 2  Used to form nouns denoting descendants of a specified historical person, especially a biblical figure.