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-ium

American  
  1. a suffix found on nouns borrowed from Latin, especially 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 Gk -ion (pericardium ).


-ium British  

suffix

  1. indicating a metallic element

    platinum

    barium

  2. (in chemistry) indicating groups forming positive ions

    ammonium chloride

    hydroxonium ion

  3. indicating a biological structure

    syncytium

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of -ium

< New Latin, Latin, neuter suffix

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Calcar -ium; pl. ia: a movable spur or spine-like process: specifically the spines at the apex of a tibia.

From Explanation of Terms Used in Entomology by Smith, John. B.

Exuvia -iae -ium: the cast skin of a larval insect: in Diaspinae the larval skin when cast and incorporated in the scale.

From Explanation of Terms Used in Entomology by Smith, John. B.

Many Consonant-Stems have so far adapted themselves to the inflection of ĭ-stems as to take -ium in the Genitive Plural, and -īs in the Accusative Plural.

From New Latin Grammar by Bennett, Charles E. (Charles Edwin)

Nom. sedīlia animālia calcāria -ia Gen. sedīlium animālium calcārium -ium Dat. sedīlibus animālibus calcāribus -ibus Acc. sedīlia animālia calcāria -ia Voc. sedīlia animālia calcāria -ia Abl. sedīlibus animālibus calcāribus -ibus 1.

From New Latin Grammar by Bennett, Charles E. (Charles Edwin)

Accent, 6; —— in gen. of nouns in -ius and -ium, 25, 1 and 2. accidit ut, 297, 2. accidit quod, 299, 1, b.

From New Latin Grammar by Bennett, Charles E. (Charles Edwin)