mud·​sill ˈməd-ˌsil How to pronounce mudsill (audio)
: a supporting sill (as of a building or bridge) resting directly on a base and especially the earth
: a person of the lowest social level

Examples of mudsill in a Sentence

Recent Examples on the Web To stop cold air from blowing into the basement or crawlspace, fill any gaps under the mudsill with expanding foam sealant. Joseph Truini, Popular Mechanics, 17 Feb. 2021 The floor frame of a shed includes the mudsill, floor joists and perimeter band joists. Joseph Truini, Popular Mechanics, 18 Mar. 2021 Then, cut pieces of fiberglass insulation or rigid polystryrene foam to fit tightly between the floor joists and up against the rim joist, which is the wide board that sits on-edge on top of the mudsill. Joseph Truini, Popular Mechanics, 17 Feb. 2021

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

Word History

First Known Use

1685, in the meaning defined at sense 1

Time Traveler
The first known use of mudsill was in 1685

Dictionary Entries Near mudsill

Cite this Entry

“Mudsill.” Dictionary, Merriam-Webster, Accessed 21 May. 2024.

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