Jesuit n.

personal name of the Christian Savior, late 12c.; it is the Greek form of Joshua, used variously in translations of the Bible. From Late Latin Iesus (properly pronounced as three syllables), from Greek Iesous, which is an attempt to render into Greek the Aramaic (Semitic) proper name Jeshua (Hebrew Yeshua, Yoshua) "Jah is salvation." This was a common Jewish personal name during the Hellenizing period; it is the later form of Hebrew Yehoshua (see Joshua).

Old English used hælend "savior." The common Middle English form was Jesu/Iesu, from the Old French objective case form, from Latin oblique form Iesu (genitive, dative, ablative, vocative), surviving in some invocations. As an oath, attested from late 14c. For Jesus H. Christ (1924), see I.H.S. First record of Jesus freak is from 1970.