What is Passover? Where does the word come from?

The Seder is the special meal that celebrates Passover

Pass·o·ver

[pas-oh-ver, pahs-] 
noun
1.
Also called PesachPesah. a Jewish festival that commemorates the exodus of the Jews from Egypt and is marked chiefly by the Seder ritual and the eating of matzoth. It begins on the 14th day of Nisan and is celebrated for eight days by Orthodox and Conservative Jews outside of Israel and for seven days by Reform Jews and Jews in Israel.
2.
(lowercasepaschal lamb (def. 1).
Origin: 
1520–30; noun use of verb phrase pass over, as translation of Hebrew pesaḥ
Dictionary.com Unabridged Based on the Random House Dictionary, © Random House, Inc. 2013. 
The Passover story is told in the Book of Exodus, Chapter 12 in the Torah
See here for a short summary of Passover traditions.

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