What does spicula mean?
Spicula is a specialized noun for a small, sharp, needle-like structure or instrument. Its best-known use is zoological: sponges may have a skeleton made of calcareous or siliceous spicules, and spicula also occurs in the hard structures of other small organisms. In mineralogy, related usage refers to needle-shaped crystalline bodies. Medical terminology has also used spicula for slender pointed instruments employed in lancing or removing material from a cavity. The noun is uncommon outside technical writing, and spicula is especially frequent in the plural, either as the plural of spicule or in the form spiculae. This distribution makes the word look more familiar to specialists than to general readers. Its Latin origin, a diminutive of spica, meaning “ear of grain” or “spike,” also neatly reflects its basic meaning: something pointed and slender.
nounA spicula is a small, sharp, needle-like structure or instrument. The term is used especially for the pointed elements of a sponge's skeleton, for acicular crystalline bodies, and for slender pointed surgical instruments.
- A minute, pointed skeletal element, especially one of the calcareous or siliceous elements supporting a sponge.
- A needle-shaped crystalline body or mineral splinter.
- A slender pointed surgical instrument used for lancing tissue or removing material from a cavity.
"Each spicula in the sponge's skeleton is shaped like a tiny needle."
"Each spicula in the sponge's skeleton is shaped like a tiny needle."
"The geologist identified a slender spicula embedded in the crystalline rock."
When spicula is treated as a singular noun, spiculae is the standard plural and spicules is also used. In scientific prose, spicula itself is frequently used as a plural, especially for the skeletal elements of sponges.
"The sponge has a supporting framework of calcareous spiculae."
A sponge may look soft, but its spicula can form a rigid skeleton of microscopic needles.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does spicula come from?
Spicula derives from Latin spīcula, a diminutive of spīca, meaning “ear of grain” or “spike.” The word entered English during the early modern period and was applied to small pointed structures and instruments. Its wider family includes spicule, spiculate, spicate, and spike, all reflecting the same basic Latin root.
Related word forms
How spicula is actually used
This is a rare technical noun used chiefly in zoology, mineralogy, and medicine. It is especially common in the plural, either as spicula or as spiculae, and plural subjects normally take plural verbs.
Easily confused with spicula
Spicule is usually the singular form, while spicula commonly serves as its plural, although some dictionaries also allow spicula as a singular noun.
In surgical terminology, spiculum denotes a slender pointed instrument, and spicula is traditionally its plural.