tzi·tzit or zi·zith (ts?-ts?t?, ts?t?s?s)pl.n. Judaism 1. The knotted tassels of thread, symbolizing the 613 commandments in the Hebrew Scriptures, attached to the corners of a tallit or other garment.2. An undergarment bearing these tassels, worn by men or boys. Used with a singular verb.[Hebrew ?î??t, tassel, fringe; see ?y in Semitic roots.]American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.tzitzit (?ts?ts?t; Hebrew tsit?si?t) pl n (Judaism) the fringes or tassels on the corners of the tallit[from Hebrew, literally: tassel]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014