The study or practice of alchemy and early chemistry (archaic); or practitioners of these arts collectively.
From 'chymic' (alchemical) + '-s' forming a noun of practice. This term parallels how 'physics' or 'ethics' work—the -ics suffix turning an adjective into an abstract field of study or practice.
Calling yourself a 'chymicist' or studying 'chymics' in the 1600s was actually cutting-edge and dangerous—you were experimenting with caustic substances, explosive reactions, and ideas the Church wasn't always comfortable with, making early chemists some of history's first mad scientists.
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