plural pilei
ˈpī-lē-ˌī 
1
: a pointed or close-fitting cap worn by ancient Romans
2
: the convex, concave, or flattened spore-bearing structure of some basidiomycetes that is attached superiorly to the stem and typically is expanded with gills or pores on the underside
called also cap
Examples of pileus in a Sentence
Recent Examples on the Web
Many historians trace it to the pileus, a cap worn by the formerly enslaved in ancient Rome to indicate that they had been freed.
—
Greg Daugherty, Smithsonian Magazine, 18 June 2024
In certain types of clouds (pileus, lenticular, and certain types of cirrus), brilliant colors can be seen.
—Marshall Shepherd, Forbes, 22 Jan. 2023
But Tuesday’s storms had something a little special: a pileus.
—Matthew Cappucci, Washington Post, 9 Aug. 2022
The species of the comb jellies that now cover the sand is Pleurobrachia pileus, and this is not the first time a massive group of them has washed up on a beach.
—Mike Wehner, BGR, 5 June 2021
By the 14th century, pileus caps were becoming taller and more cylindrical, similar to a modern chef’s hat but shorter.
—National Geographic, 11 June 2020
This style, the pileus rotundus, was adopted mainly by university students studying law, medicine, and the sciences.
—National Geographic, 11 June 2020
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Greg Daugherty, Smithsonian Magazine, 18 June 2024
In certain types of clouds (pileus, lenticular, and certain types of cirrus), brilliant colors can be seen.
—Marshall Shepherd, Forbes, 22 Jan. 2023
But Tuesday’s storms had something a little special: a pileus.
—Matthew Cappucci, Washington Post, 9 Aug. 2022
The species of the comb jellies that now cover the sand is Pleurobrachia pileus, and this is not the first time a massive group of them has washed up on a beach.
—Mike Wehner, BGR, 5 June 2021
By the 14th century, pileus caps were becoming taller and more cylindrical, similar to a modern chef’s hat but shorter.
—National Geographic, 11 June 2020
This style, the pileus rotundus, was adopted mainly by university students studying law, medicine, and the sciences.
—National Geographic, 11 June 2020
Dictionary Entries Near pileus
Cite this Entry
“Pileus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pileus. Accessed 29 Nov. 2024.
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