[1640–50; ‹ L: hospitable reception, entertainment, place of entertainment, equiv.to hospit- (s. of hospes) host, guest, stranger + -ium -ium]This word is first recorded in the period 1640–50. Other words that entered Englishat around the same time include: elevator, generator, selection, submarine, tonic-ium is a suffix found on nouns borrowed from Latin, esp. derivatives of verbs (odium; tedium; colloquium; delirium), deverbal compounds with the initial element denoting the object of the verb (nasturtium), other types of compounds (equilibrium; millennium), and derivatives of personal nouns, often denoting the associated status or office(collegium; consortium; magisterium); -ium also occurs in scientific coinages on a Latin model, as in names of metallic elements(barium; titanium) and as a Latinization of Greek -ion (pericardium)