cilium

noun

cil·​i·​um ˈsi-lē-əm How to pronounce cilium (audio)
plural cilia ˈsi-lē-ə How to pronounce cilium (audio)
1
: a minute short hairlike process often forming part of a fringe
especially : one on a cell that is capable of lashing movement and serves especially in free unicellular organisms to produce locomotion or in higher forms a current of fluid
2

Examples of cilium in a Sentence

Recent Examples on the Web One tiny flick of a microscopic cellular hair, known as a cilium, can’t do much on its own. Saugat Bolakhe, Scientific American, 11 July 2022 Once the voltage is reversed, the oxygen is driven out of the platinum—and the cilium returns to its original shape. Saugat Bolakhe, Scientific American, 11 July 2022 Mechanical interactions that began at the level of a single cilium, and then multiplied over millions of cells and extended to higher levels of structure, fully explained the coordinated locomotion of the entire animal. Quanta Magazine, 16 Mar. 2022 Cilia are found throughout our bodies, but only a small number of kinds of cells have more than one cilium apiece. Caroline Delbert, Popular Mechanics, 30 Dec. 2019 When those cilia become paralyzed, they are rendered unable to do their job protecting the lungs, and this increases your risk of infection, like pneumonia. Maggie O'Neill, Health.com, 12 Sep. 2019 Among their design concerns were methods for nurturing cilium and for recycling sweat. Guy Trebay, New York Times, 26 Sep. 2017

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'cilium.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

New Latin, from Latin, eyelid; akin to Latin celare to conceal — more at hell

First Known Use

1794, in the meaning defined at sense 1

Time Traveler
The first known use of cilium was in 1794

Dictionary Entries Near cilium

Cite this Entry

“Cilium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cilium. Accessed 19 Mar. 2024.

Kids Definition

cilium

noun
cil·​i·​um ˈsil-ē-əm How to pronounce cilium (audio)
plural cilia -ē-ə How to pronounce cilium (audio)
1
: one of the tiny hairlike structures of many cells that make lashing movements
2

Medical Definition

cilium

noun
cil·​i·​um ˈsil-ē-əm How to pronounce cilium (audio)
plural cilia -ē-ə How to pronounce cilium (audio)
1
2
: a minute, short, hairlike process that projects from the surface of most eukaryotic cells, is composed chiefly of microtubules, in unicellular organisms functions chiefly in locomotion, and in higher forms serves especially in the movement of fluids and particles (as the passage of mucus and dust from the lungs) and in sensory reception see ciliopathy

More from Merriam-Webster on cilium

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!