Modern Arabic mathematical notation - Wikipedia
ص From the Arabic ... From م mīm, which is in turn derived from متر mitr "meter" centimeter: cm: سم From سم sīn-mīm, which is in turn derived from سنتيمتر "centimeter" millimeter: mm: مم From مم mīm-mīm, which is in turn derived from مليمتر millīmitr "millimeter" kilometer: km: كم From كم kāf-mīm; also ( كلم ...
