Tzitz

The priestly crown or frontlet (צִיץ ṣîṣ/tsiyts) was the golden plate or tiara worn by the Jewish High Priest on his mitre or turban whenever he would minister in the Tabernacle or the Temple in Jerusalem.

The Hebrew noun tziytz (צִיץ) usually means "flower" or "blossom." as in "All flesh is grass and all the goodliness thereof is as the flower (tziytz) of the field." The term is used not just for the tiara of the priest, but also for flowers carved on the fittings of Solomon's Temple (1 Kings 6:35). The Greek Septuagint renders the word in Exodus 28:36 and elsewhere petalos (πέταλος), "blossom," from which the English "petal" derives.

The commandment regarding the crown is found in Exodus 28:36-38:

^[36] And thou shalt make a plate of pure gold, and engrave upon it, like the engravings of a signet: HOLY TO THE LORD. ^[37] And thou shalt put it on a thread of blue, and it shall be upon the mitre; upon the forefront of the mitre it shall be. ^[38] And it shall be upon Aaron's forehead, and Aaron shall bear the iniquity committed in the holy things, which the children of Israel shall hallow, even in all their holy gifts; and it shall be always upon his forehead, that they may be accepted before the LORD.

The Tzitz was a small rectangular plate of solid gold, engraved in Hebrew letters with "HOLINESS TO THE LORD," and having holes drilled in each of the four corners through which blue cords were threaded (Exodus 39:31) which held the tiara onto the High Priest's priestly turban. Traditionally, it is understood that one set of cords went around the High priest's head at the base of the tiara, and the other went over the forehead, all meeting at the back of the head to hold the tiara in place.

Exodus 39:30 refers to the tziytz as the "holy crown".

According to the Talmud, the wearing of the golden frontlet atoned for the sin of arrogance on the part of the Children of Israel (B.Zevachim 88b).

...
Wikipedia