Vestment in this sense often indicates clothing specific to clergy or religious ceremonies. During the ordination, each candidate was adorned with the sacred vestment.
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Denominational Variance
Different religions or denominations have unique vestments with specific names and designs. The deacon's vestments differs markedly from that of a bishop.
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Color Symbolism
The color of a vestment often has symbolic meaning within religious events. The priest's purple vestment represents penitence during Lent.