In ancient Greek geometry, the Ostomachion, also known as loculus Archimedius (from Latin 'Archimedes' box') or syntomachion, is a mathematical treatise attributed to Archimedes. This work has survived fragmentarily in an Arabic version and a copy, the Archimedes Palimpsest, of the original ancient Greek text made in Byzantine times.
The word Ostomachion (Ὀστομάχιον) comes from Greek ὀστέον (osteon) 'bone' and μάχη (mache) 'fight, battle, combat'. The manuscripts refer to the word as "Stomachion", an apparent corruption of the original Greek. Ausonius gives us the correct name "Ostomachion" (quod Graeci ostomachion vocavere, "which the Greeks called ostomachion").