• -ium

    Origin

    From Latin -um ("neuter singular morphological suffix"), based on Latin terms for metals, such as ferrum.

    Full definition of -ium

    Suffix

    1. Used to form the names of metal elements, after the style of early-named elements, as well as the isotopes of hydrogen.
    2. By extension, appended to common words to create scientific-sounding or humorous-sounding fictional substance names.
      • 2009, Selena Kitt, Quickies, p. 91:We're at the North Pole, aren't we? Let's just call the new element Santa Clausium!
      • 2007, Jason Lethcoe, Wishing Well, appendix p. ii:Stupidium: Exposure to this Element can cause very silly behavior.
      • 1997, Bryan Pfaffenberger, Official Microsoft Internet Explorer 4 book, p. 34:According to the FAQ, a site's coolness can be attributed to a trace element called coolium.
    3. Used to indicate the setting where a given activity is carried out: gymnasium, auditorium, stadium, colloquium, planetarium, podium, sanatorium. Words so formed often take "-a" for the plural.
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