Spiced salted pressed and air dried beef, water buffalo or camel meat, similar to the Italian bresaola.
The word comes from the Turkish bastırmak (to press), although a similar style of meat was probably made in Byantine times. It was brought to Northern Greece after the population exchange in 1923, where it's eaten in thin slices, or used to flavour chick peas, served with eggs, or stuffed in pies, etc.
Image by RosarioVanTulpe, Creative Commons License