Tanzania, the country

Tan, or Dān (聃), is the posthumous name of Lao Zi (Lao Tzu).

Tanning, the process of making leather from hides

Tan is the nickname Riley Martin gave to the Biaviian alien O-Qua Tangin Wann, who is listed as the co-author of Martin's book, The Coming of Tan.

Sun tanning, the darkening of skin in response to ultraviolet light

OS-tan, an Internet phenomenon on Futaba Channel.

Tangent, a mathematical trigonometric function tan(x)

The Anime Network, an all-anime channel

Tan (or Tanfana, Tamfana), ancient European goddess

Transaction authentication number in electronic banking

Tan (surname) (譚), a Chinese surname

Tan (color), the color

Total Acid Number, the measure of a lubricant's or crude oil's acidity

TAN Books & Publishers, a Catholic publishing company

Thunderbirds Are Now!, a Detroit-based neo-post-punk band

Tahn, a yoghurt-based drink from the Middle East

Taunton Municipal Airport (IATA airport code), in Taunton, Massachusetts