From Latin 'arma' (weapons) + 'sistere' (to stop) — literally 'a stopping of arms,' with the same '-stitium' as in 'solstice.'
An agreement to stop fighting temporarily, especially as a prelude to peace negotiations.
From French armistice or New Latin armistitium, a 17th-century learned coinage from Latin arma (weapons, arms) + -stitium (a stopping, a suspension), from sistere (to cause to stand still), from PIE *steh₂- (to stand). The -stitium element also appears in solstice (sol + stitium, the sun standing still) and interstitium (the space between). Arma derives from PIE *h₂er- (to fit together), the root
German 'Waffenstillstand' (weapon-standstill) is a perfect calque of 'armistice' — both mean exactly 'arms standing still.' The '-stitium' in armistice is the same element in 'solstice,' where the sun appears to 'stand still' at its turning points. So an armistice is when weapons have their solstice