Ἰουδαϊσμός G2454
Ioudaïsmós · ee-oo-dah-is-mos' · Noun Masculine
from Ἰουδαΐζω; "Judaism", i.e. the Jewish faith and usages:--Jews' religion.
2 Occurrences in the King James Bible
Galatians 1:13For ye have heard of my conversation in time past in the Jews’ religion, how that beyond measure I persecuted the church of God, and wasted it:
Galatians 1:14And profited in the Jews’ religion above many my equals in mine own nation, being more exceedingly zealous of the traditions of my fathers.