Rei is both a Japanese given name and a Hebrew given name.
In Japanese it could have different meanings depending on the used kanji and can be used for (or by) either gender.
In Hebrew, the name Rei (רעי Re`eeY) originates in biblical texts which mean "my shepherd; my companion; my friend".
In the Hebrew Bible, Rei is an Israelite loyal to King David at the time of the usurpation of Adonijah, who remained firm to David's cause when Adonijah rebelled.
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