Etymology: < classical Latin -facient-, -faciēns ‘making’, present participle of -facere, used in compounds (e.g. calefacere , stupefacere ) of facere to make (see fact n.) where the first element is a verb in -ēre . Compare facient n.This termination is found from the 17th cent. in nouns and adjectives borrowed from the present participles of Latin verbs in -facere , earliest in calefacient n., stupefacient adj. Formations in English are found from the early 19th cent., and are frequent from the middle of that century, especially in the vocabulary of science and medicine. The element occurs from the first half of the 19th cent. in English formations < Latin verbs in -ere where no verb in -facere exists (as sorbefacient adj.) and from a similar date in formations < Latin verbs in -ire (as parturifacient n.) and from Latin nouns (as e.g. febrifacient adj.). Since English verbs in -fy suffix are formed < Latin verbs in both -facere and -ficāre -ficate comb. form ( < -ficus -fic suffix), English adjectives in -facient sometimes have equivalents in -fic suffix, as e.g. febrifacient adj. (beside earlier febrific adj.), calorifacient adj. (beside earlier calorific adj.). Formations < English nouns and combining forms of Latin origin are also occasionally found from the late 19th cent., as e.g. somnifacient adj., immunifacient adj. N.E.D. (1894) comments on the pronunciation: ‘Some pronounce (fēi·ʃĕnt) /ˈfeɪʃənt/, but (fēi·ʃiĕnt) /ˈfeɪʃɪənt/ or (fēi·ʃyĕnt) /ˈfeɪʃjənt/ is more usual.’
This entry has been updated (OED Third Edition, September 2009; most recently modified version published online June 2021).