Clerical clothing is non-liturgical clothing worn exclusively by clergy. It is distinct from vestments in that it is not reserved specifically for use in the liturgy. Practices vary: clerical clothing is sometimes worn under vestments, and sometimes as the everyday clothing or street wear of a priest, minister, or other clergy member. In some cases, it can be similar or identical to the habit of a monk or nun.
In modern times, many Christian clergy have adopted the use of a shirt with a clerical collar; but the use of clerical clothing is most commonly among Catholic, Anglican, Oriental Orthodox, and Eastern Orthodox clergy.
Catholicism
In 1215, the Fourth Lateran Council made it mandatory for all the Christian clergy to wear distinctive dress. Its purpose was not necessary to elevate the status of the Christian clerics; it was intended that they would catch the public eye if any member of the clergy is seen on the street. However, the rules at the time were not the same as the modern rules, and the rules vary by jurisdiction.
Cassock: A long-sleeved, hoodless garment. Depending on the climate it can be made of very lightweight material or heavy wool. In tropical climates white is worn. This is the norm for secular clergy and members of religious institutes. Some religious societies such as the Jesuits and Redemptorists wear their own style of the cassock. Monks and friars wear a habit that can differ considerably from the cassock. Cassocks are generally ankle-length. The color is black for priests, black with purple piping for canons, black with magenta piping for monsignors, black with amaranth red piping for bishops; and black with scarlet red for cardinals. The Roman Pontiff wears a white cassock. Monsignors, bishops and cardinals have what is known as a "choir cassock" for liturgical occasions but this is not worn for everyday wear. Ferraiolo: A full-length cape reaching to the ankles. This is only worn with the cassock on formal white tie or Morning dress occasions. Cape: A covering for the cassock in cold weather. Greca (clothing) (douillette): An overcoat covering the cassock. Hat: zucchetto or biretta, depending on circumstance. Clerical collar: There are a variety of options for daily clerical attire, all involving the use of a clerical collar: Collarino (Tab Collar): This is probably the most common type of shirt and collar among Roman-rite Catholic clergy. It resembles a standard dress shirt but has a standing black collar that is sewn to accommodate a white cloth or soft plastic insert, leaving a small white square at the base of the throat. Neckband: A collarless shirt (similar to a banded collar shirt) tailored to accommodate a strip of linen or plastic that, when worn over the shirt, creates a standing white collar that rings the neck. This detachable collar is fastened with collar stays or buttons. These shirts and detachable collars were originally intended to be worn underneath a waistcoat, rabat, or cassock. Today these shirts are almost invariably black poly-cotton, but when worn under a waistcoat or rabat are usually white and made of a higher quality oxford cotton weave. Clerical waistcoat or rabat: Clerical waistcoats or rabats are the most traditional and formal item of clerical costume. They are almost always black and are made of worsted wool. Clerical waistcoats generally sport silk backing. They are worn over a neckband shirt and a detachable collar to create a cassock-like appearance about the neck. Unlike the waistcoats that accompany suits, they button all the way to the collar. The rabat is a late innovation, and exactly mirrors the clerical waistcoat, except that it is backless.
Eastern Christianity
In the Eastern Catholic Churches and Eastern Orthodox Churches a useful distinction between liturgical vestments and clerical clothing is that vestments are required to be blessed before being worn. Conversely, clerical clothing is not, and is regarded as daily wear.
Inner cassock: The inner cassock (or simply, cassock) is a floor-length garment, usually black, worn by all clergy members, monastics, and seminarians. Outer cassock: Called a () or , the outer cassock is a large flowing garment worn over the inner cassock by bishops, priests, deacons, and monastics. : A soft-sided cap worn by monastics or awarded to clergy as a mark of honor. : A stiff hat worn by monastics or awarded to clergy as a mark of honor. : A veil worn either by nuns, either alone or with a . : A veil extending over the back, worn with the by all monastics and bishops. : A with an permanently attached; more common in the Russian tradition.