Armband
An armband was a device or a piece of material which was worn around the arm, over the sleeve of other clothing if present. Members of the Nazi Party, the Cult of the Pah-wraiths, and the Romulan Rebirth movement all wore armbands as part of their uniforms, to show the allegiance of the wearers. (In the case of the Romulan Rebirth movement, their armbands were the only consistent aspect of their attire) (; ; )

Nyota Uhura once wore a black fabric armband at her communications station on the bridge of the  in 2267. ()
Technological armbands creating an antipolaric field were worn by a landing party from the , while surveying Makull's homeworld in 2371. ()

See also 
 Emergency transporter armband
Technology
Clothing accessories