sill
noun
a horizontal timber, block, or the like serving as a foundation of a wall, house, etc.
sill
1 American
[sil]
/ sɪl /
noun
-
sills
plural
-
a horizontal timber, block, or the like serving as a foundation of a wall, house, etc.
-
the horizontal piece or member beneath a window, door, or other opening.
-
Geology. a tabular body of intrusive igneous rock, ordinarily between beds of sedimentary rocks or layers of volcanic ejecta.
Sill
2
American
[sil]
/ sɪl /
noun
sill
British
/ sɪl /
noun
-
a shelf at the bottom of a window inside a room
-
a horizontal piece along the outside lower member of a window, that throws water clear of the wall below
-
the lower horizontal member of a window or door frame
-
a continuous horizontal member placed on top of a foundation wall in order to carry a timber framework
-
a flat usually horizontal mass of igneous rock, situated between two layers of older sedimentary rock, that was formed by an intrusion of magma
sill
Scientific
/ sĭl /
Other Word Forms
Derived Forms
Inflected Forms
Nouns
Etymology
Origin of sill
before 900; Middle English sille, Old English syl, sylle; cognate with Low German süll, Old Norse syll; akin to German Schwelle sill
Vocabulary lists containing sill
Earth Science - Middle School
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Earth Science - High School
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Rocks and Minerals - Middle School and High School
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
The Red Sea was initially connected from the north to the Mediterranean through a shallow sill.
From Science Daily ● Oct. 8, 2025
Often it seems, this cosy spot would appear to be a window sill, as ladybirds can easily squeeze through the small gaps around loose fitting windows.
From BBC ● Oct. 7, 2025
“It’s the law,” the not-unkind super replies — though Alex, now 2, can barely sit up, let alone reach the sill.
From New York Times ● Apr. 23, 2024
They’re sill exploring options, including possibly lending it to the L.A.
From Los Angeles Times ● Mar. 11, 2024
A ladder had appeared, propped against the sill of an upstairs bedroom window.
From "A Long Way from Chicago" by Richard Peck
Sill, Emanuel concludes: “With none of the flags pointing to elevated systemic risks, EVR ISI Strategy continues to see S&P 500 ending 2026 at 7,750, with the potential for a bubble forming at 30%.”
From MarketWatch ● Dec. 29, 2025
The trunk and benches were hidden behind curtains while they were being installed at The Sill, which is just two miles from where the tree had stood.
From BBC ● Jul. 10, 2025
In the mountains east of San Diego, a wind gust of 102 mph was recorded at Sill Hill, nearing the all-time record of 105 mph recorded there on Feb. 26, 2020, Tardy said.
From Los Angeles Times ● Jan. 22, 2025
Sill says people always reach out with funny questions about what exactly they can store.
From Seattle Times ● May 17, 2024
Known as Wally, she was a flight instructor at Fort Sill, an army base in southwestern Oklahoma, when she picked up the Life magazine featuring Jerrie Cobb.
From "Women in Space" by Karen Bush Gibson
I have so many books, but never enough shelves, so I have books everywhere — piled up on tables, chairs, running along window sills, books in every available nook and cranny.
From New York Times ● May 9, 2024
Snow gently piled on window sills and in corners didn’t melt, revealing one piece of trivia most Hallmark aficionados have long known.
From Salon ● Dec. 23, 2023
Eventually, all that water poured into Planada, rushing into town in the dark, surrounding people’s homes, rising up in their yards, eventually seeping in under door frames and window sills.
From Los Angeles Times ● Dec. 18, 2023
These levels would be 3 micrograms per square foot on the floor and 20 micrograms per square foot for sills.
From Seattle Times ● Jul. 12, 2023
Three towers, each topped with a dome in dusky pink, gave it a look of wit and knowing intelligence, and its vast arched windows with their broad sills gave it solidity and purpose.
From "Impossible Creatures" by Katherine Rundell
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
