Analysis of information sources in references of the Wikipedia article "Nicodemite" in English language version.
[...] a secret follower or adherent[;] specifically : a 16th century Protestant Christian who lived in a Roman Catholic country and escaped persecution by concealing his or her Protestantism
The term Nicodemite, derived from Nicodemus, who visited Jesus by night, generally denotes a secret or timid adherent. J. Calvin applied it to those converts to Protestantism in Catholic France who outwardly continued RC practices. In modern times Nicodemism covers all forms of religious simulation.