Thanaka is a yellowish-white cosmetic

Cosmetics

Cosmetics are substances used to enhance the appearance or odor of the human body. Cosmetics include skin-care creams, lotions, powders, perfumes, lipsticks, fingernail and toe nail polish, eye and facial makeup, towelettes, permanent waves, colored contact lenses, hair colors, hair sprays and...

 paste made from ground bark. It is a distinctive feature of Myanmar

Myanmar

Burma , officially the Republic of the Union of Myanmar , is a country in Southeast Asia. Burma is bordered by China on the northeast, Laos on the east, Thailand on the southeast, Bangladesh on the west, India on the northwest, the Bay of Bengal to the southwest, and the Andaman Sea on the south....

 (formerly Burma) seen commonly applied to the face and sometimes the arms of women and girls and to a lesser extent men and boys. The use of thanaka has also spread to neighboring countries including Thailand

Thailand

Thailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the...

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The earliest literary reference to thanaka is in a 14th century poem written by Mon-speaking

Mon people

The Mon are an ethnic group from Burma , living mostly in Mon State, Bago Division, the Irrawaddy Delta, and along the southern Thai–Burmese border. One of the earliest peoples to reside in Southeast Asia, the Mon were responsible for the spread of Theravada Buddhism in Burma and Thailand...

 King Razadarit's consort.