A stringed instrument that is played as a folk instrument in Macedonia and Bulgaria. It has doubled steel strings and is played with a plectrum, in the same manner as a mandolin.
The Bulgarian tambura (pictured) has 8 steel strings in 4 doubled courses. All the courses are tuned in unison, with no octaves. It is tuned D3 D3, G3 G3, B3 B3, E4 E4. It has a floating bridge and a metal tailpiece. The instrument body is often carved from a single block of wood and is therefore quite heavy.
The Macedonian tambura has 4 steel strings in 2 doubled courses. It is tuned A A , D D (or another pitch but at the same relative intervals of a fourth) when playing melodies based on A tonic upon A drone. It also may be tuned G G , D D (or another pitch but at the same relative intervals of a fifth) when playing melodies based on G tonic upon G drone. Sometimes octave strings are used on the lower course. It has a floating bridge and a metal tailpeice. The instrument body is more often made from staves like a lute.
Note that the Indian tanpura is sometimes spelled as tambura or tamboura. The one album credit seems more likely to be the European instrument, but this is not certain.