Thinking of costume ideas for a fancy dress party can be hard, and especially so if you're attending a themed party, such as that of nuns and vicars. This makes coming up with a good costume much harder because you know there are going to be many people at the party wearing the same basic costume as you. However, coming up with a few original ideas for a nun costume is a good way to stand out at the fancy dress party.
You can buy a simple nun costume from most fancy dress shops; they generally consist of a black and white veil and a black gown known as a habit. The ankle-length gown covers the entire body and the black and white veil drapes down from the top of the head onto the shoulders, covering both the back and sides of the head. This "basic" nun look is a good fallback idea if you are short of time or money and are looking to put together an easy costume. There are also a few accessories that you can carry to set your costume apart, such as a rosary and a Bible.
Nuns are sexually abstinent, which makes dressing up as a sexy nun a way to have fun with the basic idea and add a darker side to your costume. Sexy nun costumes are similar in design to the basic nun costume, but consist of significantly less material. Instead of a gown, pair a black low-cut top and a short black skirt with the veil and accessories. These costumes are also available from many fancy dress shops and websites. White, high stockings add an extra element to the costume.
Dressing as a pregnant nun is the logical step forward from the sexy nun, embodying essentially the same joke but from a different angle. You can buy a fake pregnant belly, or alternatively use a balloon or cushion to create your pregnant belly. "Basic" nun habits generally contain a lot of material, so adding a fake belly into a normal nun costume is unlikely to cause a logistical problem, and it may raise a few laughs.
Historically Accurate Nun
Instead of wearing a basic nun costume, you could emulate famous nuns such as Mother Teresa and Saint Bridget of Ireland. A Mother Teresa costume involves a white habit, a white headdress with a blue band across the forehead, a cardigan sweater and the carrying of rosary beads. As Saint Bridget, wear a black habit, translucent black veil and white neck-scarf. Paying attention to detail and dressing as one specific historical nun is a great way to stand out at a nuns and vicars party, and can be done relatively easily. See Resources for information on other famous historical nuns.
One of the easiest variations you can come up with on a costume is to make it a zombie costume. Wearing a basic nun outfit and adding some fake blood, pallid white face paint, and dark circles around the eyes is enough to create a zombie nun. A few rips can be added to the gown as additional detail.