Arabic al-kīmiyaʾ or al-khīmiyaʾ ( or ), according to some, is thought to derive from the Koine Greek word khymeia () meaning "the art of alloying metals, alchemy"; in the manuscripts, this word is also written khēmeia () or kheimeia (), which is the probable basis of the Arabic form. According to Mahn, the Greek word χυμεία khumeia originally meant "cast together", "casting together", "weld", "alloy", etc. (cf. Gk. kheein () "to pour"; khuma (), "that which is poured out, an ingot"). Assuming a Greek origin, chemistry is defined as follows:
:Chemistry, from the Greek word  (khēmeia) meaning "cast together" or "pour together", is the science of matter at the atomic to molecular scale, dealing primarily with  collections of atoms, such as molecules, crystals, and metals.