Thaar

Onnara is a form of underwear for women of all ages. It is the traditional underwear among the Hindu women in Kerala (the southern most state of India).

A cotton (handloom) cloth of size 6 muzham × 3 muzham (1 muzam = 1.5 ft approximately) is used to drape around the waist, in a particular style) under the outer garment (pavada, saree, or mundu).

Onnara is also called thaar in some parts of the state. The word is more often used in the southern part of Kerala; onnara is mostly a northern Kerala usage. However, there are certain differences in wearing thaar, over Onnara. Thaar is simpler than the onnara in the wearing style. There are different types of thaar too.

In olden days, the tradition said that the people should visit the temple in the morning and evening, wearing onnara because having a dip and coming to temple with wet garments was strictly prohibited as it exhibited the body parts to others. Both men and women wore it, but women in particular wore it at home and as an inner garment while going out.

Nowadays it is increasingly being uses by women of all classes of society. Onnara (thaar) is an undergarment for women, and is not for males.

Onnara provides enough support and covers the vulva completely giving enough space for absorption of secretions and at the same time gives ample space for free air circulation as it is worn loose in those areas. Even during menstruation, it prevents side way leakage and feel of uneasiness due to its breadth.

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Wikipedia