The first syllable of alchemy is a grammar word. In Arabic, al- means "the," so al-kimiya is "the kimiya." English took the article along with the noun, which is why alchemy begins the way it does.

The harder question is where the rest comes from. Merriam-Webster says Arabic kīmiyāʾ may have passed through Syriac from Late Greek chēmeia or chymeia, and that the Greek form's origin is uncertain. Two explanations compete.

One ties it to Egypt. Etymonline notes that Plutarch used Khemia as a name for Egypt, "land of black earth." That would make alchemy the Egyptian art, and Etymonline cites a decree of Diocletian from around 300 CE against "the old writings of the Egyptians." Merriam-Webster cautions that this edict is known only from a 7th-century chronicler, with no contemporary evidence. It adds that Zosimos of Panopolis, writing about 300 CE, connected the term with Egyptian metalworkers.

The other explanation connects it to Greek khein, "to pour." Merriam-Webster ties it to the noun khyma, "fluid" or "ingot," and Etymonline gives khymatos, "that which is poured out." Etymonline says the scholar Watkins supports this, while Klein, citing an earlier scholar, calls it folk etymology. Merriam-Webster treats the question as undecided, and neither theory has won.

Etymonline reports one more view, attributed to Mahn in the OED. The original Greek form was probably khymeia and first described pharmaceutical work with plant juices. Alexandrian alchemy came later, and its link to Egypt's ancient name may have made the word popular.

The word reached Europe through Arabic Spain and into English by the mid-14th century. For hundreds of years it was simply medieval chemistry, a mix of occult philosophy and practical metallurgy.

After about 1600 the two split. Chemistry, first recorded around 1600 as a word for alchemy, took over the experimental work. Alchemy was left with the narrower dream: turning base metals into gold or silver, finding a universal solvent, and a cure for everything.

The leftovers are everywhere. Etymonline lists quintessence, refrigeration and circulation among words that began as alchemical terms.