[1820–30; mercurial + -ism]This word is first recorded in the period 1820–30. Other words that entered Englishat around the same time include: exogenous, karma, phonetic, takeoff, tetrapod-ism is a suffix appearing in loanwords from Greek, where it was used to form action nounsfrom verbs (baptism). On this model, -ism is used as a productive suffix in the formation of nouns denoting action or practice,state or condition, principles, doctrines, a usage or characteristic, devotion oradherence, etc. (criticism; barbarism; Darwinism; despotism; plagiarism; realism; witticism; intellectualism)