# -ium
## English
### Pronunciation

* Audio (US):(file)

### Etymology 1

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

#### Suffix

-ium
* (chemistry) Used to form the names of metal elements, after the style of early-named elements, as well as the isotopes of hydrogen.
* (chemistry) Used to form the temporary systematic element name of a metallic or nonmetallic element which is postulated to exist, or which has been newly synthesized and has not yet been assigned a permanent name.
* (chemistry) Used to form the name of polyatomic cations.
* (by extension, humorous) Appended to common words to create scientific-sounding or humorous-sounding fictional substance names.
** 1997, Bryan Pfaffenberger, Official Microsoft Internet Explorer 4 book, page 34:According to the FAQ, a site's coolness can be attributed to a trace element called coolium.
** 2007, Jason Lethcoe, Wishing Well, appendix, page ii:Stupidium: Exposure to this Element can cause very silly behavior.
** 2009, Selena Kitt, Quickies, page 91:We're at the North Pole, aren't we? Let's just call the new element Santa Clausium!

### Etymology 2

Reanalysis from multiple Latin or New Latin compounds suffixed with -ium, whose function, among others, is to derive parasynthetic compounds.

#### Suffix

-ium (plural -iums, irregular plural -ia)
* Used to form the name of an aggregation or mass of something, such as biological tissue
    epithelium, pollinium
* Forms the name of biological structures and parts.
    clinanthium, periodontium

### Etymology 3

Reanalysis of Latin words suffixed with -tōrium, -ārium and -ium.

#### Suffix

-ium (plural -iums, irregular plual -ia)
* Used to indicate the setting where a given activity is carried out
    auditorium, gymnasium, planetarium

### Etymology 4

Reanalysis of ammonium or from -onium of the same source.

#### Suffix

-ium
* (pharmacology) Used to form names of quaternary ammonium compounds used as neuromuscular blocking agents, cholinergic agents, anticholinergic agents, antibacterials/antiseptics, or other agents.
    Alternative form: -onium

### See also

* (Etymology 1) -um
* -ion

### Anagrams

* IMU, MUI, Miu, Mui, UIM, imu

## Danish
### Suffix

-ium
* Used to form nouns (loanwords) of Greek or Latin origin; -ium
    akvarium, evangelium, kriterium, kollegium, laboratorium, medium, privilegium, sanatorium, studium ― aquarium, gospel, criterion, college, laboratory, medium, privilege, sanatorium, study
* (chemistry) Used to form nouns denoting chemical compounds, especially elements; -ium
    barium, aluminium, beryllium, ammonium ― barium, aluminium, beryllium, ammonium
* (botany) Used to form nouns denoting plant designations; -ium
    geranium, kaprifolium ― caprifolium, geranium

#### Derived terms
### References

* “-ium” in Den Danske Ordbog

## Dutch
### Suffix

-ium
* -ium

## Latin
### Etymology 1

From -ius (suffix forming adjectives): as a nominal suffix (Suffix 1), a substantivisation of its neuter forms; as an adjectival suffix (Suffix 2), regularly declined forms. Compare Ancient Greek -ιον (-ion), Proto-Slavic *-ьje.

#### Pronunciation

* (Classical Latin) IPA: /i.um/, [iʊ̃ˑ]
* (modern Italianate Ecclesiastical) IPA: /i.um/, [ium] (stressed on the antepenult)

#### Suffix

-ium n (genitive -iī or -ī); second declension
* Suffix used to form abstract nouns, sometimes denoting offices and groups. May no longer be productive.
    ‎auspex + ‎-ium → ‎auspicium
    ‎dēsīderō + ‎-ium → ‎dēsīderium
    ‎castellum (“castle”) + ‎-ium → ‎castilium (“fortified city”)
* (New Latin) Suffix appended to form names of chemical elements.

##### Declension

Second-declension noun (neuter).
$^1$Found in older Latin (until the Augustan Age).

##### Derived terms

* aestimium
* alloquium
* ambivium
* cōnfluvium

##### Descendants

* Norwegian Bokmål: -ium

### Etymology 2

See the etymology of the corresponding lemma form.

#### Suffix

-ium
* inflection of -ius:
** nominative/accusative/vocative neuter singular
** accusative masculine singular

### Etymology 3

See the etymology of the corresponding lemma form.

#### Suffix

-ium
* genitive plural of -s

### References

* “-ium” on page 981/3 of the Oxford Latin Dictionary (1st ed., 1968–82)

## Norwegian Bokmål
### Etymology

From Latin -ium (forms names of chemical elements), from -ius (forms adjectives), from Old Latin -iōs, from Proto-Italic *-jos (forms comparative adverbs), from Proto-Indo-European *-yōs ~ *-is- (forms adjectives).

### Pronunciation

* IPA: /ɪ.ʉm/
* Audio:(file)
* Rhymes: -ʉm
* Hyphenation: -i‧um

### Suffix

-ium
* Used to form nouns (loanwords) of Greek or Latin origin; -ium
    akvarium, evangelium, kriterium, kollegium, laboratorium, medium, privilegium, sanatorium, studium ― aquarium, gospel, criterion, college, laboratory, medium, privilege, sanatorium, study
* (chemistry) Used to form nouns denoting chemical compounds, especially elements; -ium
    barium, aluminium, beryllium, ammonium ― barium, aluminium, beryllium, ammonium
* (botany) Used to form nouns denoting plant designations; -ium
    geranium ― geranium
* (geology) Used to form nouns denoting geological designations; -ium
    alluvium, kambrium, ordovicium ― alluvium, cambrium, ordovicium

### References

* “-ium” in Det Norske Akademis ordbok (NAOB).