-ium — English Dictionary

Suffix

1. Used to form the names of metal elements, after the style of early-named elements, as well as the isotopes of hydrogen.

   Usage

   • morpheme
   • Uncountable
   • usually

2. 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.

   Usage

   • morpheme
   • Uncountable
   • usually

3. Used to form the name of polyatomic cations. Common examples are quaternary ammonium compounds used as neuromuscular blocking agents, cholinergic agents, anticholinergic agents, antibacterials/antiseptics, or other agents.

   Usage

   • morpheme
   • Uncountable
   • usually

   Examples

   Alternative form: -onium

4. Appended to common words to create scientific-sounding or humorous-sounding fictional substance names.

   Usage

   • broadly
   • Humorous
   • morpheme
   • Uncountable
   • usually

   Examples

   According to the FAQ, a site's coolness can be attributed to a trace element called coolium.

   Stupidium: Exposure to this Element can cause very silly behavior.

   More examples (1)

   We're at the North Pole, aren't we? Let's just call the new element Santa Clausium!

Suffix

1. Used to form the name of an aggregation or mass of something, such as biological tissue

   Usage

   • morpheme

   Examples

   epithelium, pollinium

2. Forms the name of biological structures and parts.

   Usage

   • morpheme

   Examples

   clinanthium, periodontium

Suffix

1. Used to indicate the setting where a given activity is carried out

   Usage

   • morpheme

   Related words

   -um-ion

   Examples

   auditorium, gymnasium, planetarium