Chēm'is-try, n.

(kēm'is-trȳ) (Synop., § 130), n. [From chemist; Fr. chimie, Sp. chimia, It. & Pg. chimia, Pr. alkimia, Sp. & Pg. alquimia, from Ar. al-kimiā. See ALCHEMY.] That branch of science which treats of the composition of substances, and of the changes which they undergo.

Inorganic chemistry, that which treats of inorganic or mineral substances. — Organic chemistry, that which treats of the substances which form the structure of organized beings and their products, whether animal or vegetable. — Practical, or applied chemistry, that which treats of the modes of manufacturing the products of chemistry that are useful in the arts, of their applications to economical purposes, and of the conditions essential to their best use. — Pure chemistry, that which treats of the elemental constitution of substances, of the laws of combination, and of the mutual reactions and relations therein involved. It consequently explains the modes and proportions of composition, and the processes of decomposition and decay, and also the nature of the elements and of their compounds.

This word and its derivatives were formerly written with y, and sometimes with i, instead of e, in the first syllable, chymistry, chymist, chymical, &c., or chemistry, chimist, chimical, &c.; and the pronunciation was conformed to the orthography. At the present day, most speakers pronounce these words as they are now spelt, chem'is-try, chem'ist, chem'ic-al, &c.