spic·​ule ˈspi-(ˌ)kyül How to pronounce spicule (audio)
: a slender pointed usually hard body
especially : one of the minute calcareous or siliceous bodies that support the tissue of various invertebrates (such as sponges)
: a spikelike short-lived prominence appearing close to the chromosphere of the solar atmosphere
spicular adjective
spiculation noun

Examples of spicule in a Sentence

Recent Examples on the Web Along the solar horizon, towering spires of gas known as spicules stretch up to about 6,214 miles (10,000 kilometers) from the Sun’s chromosphere. George Dvorsky / Gizmodo, Quartz, 2 May 2024 According to a press release, the team observed the emergence of spicules while also monitoring nearby magnetic fields. Jason Daley, Smithsonian, 15 Nov. 2019 According to this new research, the same process could create the much smaller spicules. Jason Daley, Smithsonian, 15 Nov. 2019 In fact, researchers at his lab released a major model of how the spicules form in 2017. Jason Daley, Smithsonian, 15 Nov. 2019 The spicules surge thousands of miles high, passing through the chromosphere and into the sun’s corona before collapsing. Nicholas St. Fleur, New York Times, 23 June 2017

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

Word History


New Latin spicula & Latin spiculum; New Latin spicula, alteration of Latin spiculum head of a spear or arrow, diminutive of spicum, spica ear of grain

First Known Use

1785, in the meaning defined at sense 1

Time Traveler
The first known use of spicule was in 1785

Dictionary Entries Near spicule

Cite this Entry

“Spicule.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/spicule. Accessed 24 May. 2024.

Kids Definition


spic·​ule ˈspik-yü(ə)l How to pronounce spicule (audio)
: a small hard needlelike structure
especially : one of the tiny calcium- or silica-containing bodies that support the tissues of various invertebrates and especially sponges

Medical Definition


spic·​ule ˈspik-(ˌ)yü(ə)l How to pronounce spicule (audio)
: a minute slender pointed usually hard body (as of bone)

More from Merriam-Webster on spicule

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