Үнді субконтинентінің дәстүрлі қызыл құмы (синдoor)

Traditional vermilion cosmetic powder from the Indian subcontinent
the films

Sindoor (, ) or sindura is a traditional vermilion red or orange red cosmetic powder from the Indian subcontinent, usually worn by married women along the part of their hairline. In Hindu communities, the sindoor is a visual marker of marital status of a woman and ceasing to wear it usually implies widowhood. Traditional sindoor was made with turmeric and alum or lime, or from other herbal ingredients. Unlike red lead and vermilion, these are not poisonous. Some commercial sindoor products contain synthetic ingredients, some of which are not manufactured to proper standards and may contain lead.

Sindoor is traditionally applied at the beginning or completely along the parting line of a woman's hair (also called mang in Hindi or simandarekha in Sanskrit) or as a dot on the forehead. Sindoor is the mark of a married woman in Hinduism. Single women wear the bindi in different colours for special occasions but don't apply sindoor in their parting of the hairline. Widows do not wear sindoor or bindis, signifying that their husband is no longer alive. The sindoor is first applied to the woman by her husband on the day of her wedding; this is called the Sindoor Danam ceremony. After this, she applies it herself every day. A similar colouring ritual is known as pasupu kumkuma, named after another name for sindoor, kumkuma. The wiping off of the sindoor is very significant for a widow. There are many rituals associated with this practice. The most common is when a mother in law or older sister in law wipes off the sindoor when a woman becomes a widow. The widow will break her bangles and remove her bindi as well, and many will also remove their nose ring and toe rings. The parting of hair is symbolic of a river of red blood full of life. When the sindoor is removed then the river becomes barren, dry and empty. This custom is prevalent in rural areas and is followed by all castes and social ranks. The red sindoor is significant for the married woman as she is full of colour. When she becomes a widow she adopts plain white dress and removes all colour from her face including the bright red sindoor. Methods and styles of applying the sindoor vary from personal choice to regional customs. Many new brides will fill the whole hair line with sindoor, while other married women may just apply a red spot at the end of the hair line and forehead. Recently, a triangle shape on the forehead pointing towards the nose, with a diamond bindi for fashion, is being worn by younger women.

There are various forms of sindoor mentioned in Ayurveda. Traditional sindoor is made from natural ingredients used for facial makeup (cosmetics). Most widely used traditional sindoor is made from turmeric and lime juice. Other ingredients include ghee, and slaked lime. This is also called kumkuma. Sindoor is also made from red sandal powder, saffron etc. The coloured powders sold as substitutes are traditionally not considered sindoor.

Traditional sindoor was made with turmeric and alum or lime, or from other herbal ingredients. Unlike red lead and vermilion, these are not poisonous. Modern material being sold as sindoor mainly uses vermilion, an orange red pigment, the purified and powdered form of cinnabar, which is the chief form in which mercury sulfide naturally occurs. As with other compounds of mercury, sindoor is toxic and must be handled carefully. Sometimes, red lead (lead tetroxide, also known as minium) is added to sindoor. Red lead is toxic. In early 2008, allegations of high lead content led the U. S. Food and Drug Administration to recall batches of sindoor from several manufacturers.

There are many Indian movies and dramas involving sindoor, with their themes revolving around the ritual's significance. These include Sindoor (1947), Sindooram (1976), Rakta Sindhuram (1985), Sindoor (1987), and Sindoor Tere Naam Ka (series, 2005–2007).