Ἰουδαΐζω to become a Judæan, i.e. "Judaize"
Derivation: from G2453;
KJV Usage: live as the Jews. G2453
Thayer:
1) to adopt Jewish customs and rites, imitate the Jews, Judaise
1a) one who observes the ritual law of the Jews

Ἰουδαΐζω
Ioudaizō
ee-oo-dah-id'-zo
From G2453; to become a Judaean, that is, “judaize”
KJV Usage: live as the Jews.