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.
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
before 900; Middle English sille, Old English syl, sylle; cognate with Low German süll, Old Norse syll; akin to German Schwelle sill
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Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The Red Sea was initially connected from the north to the Mediterranean through a shallow sill.
From Science Daily • Oct. 8, 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
Exterior and interior halves drape over a sill to leave the window mostly unobscured.
From Seattle 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
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.
