mul·​lion | \ ˈməl-yən How to pronounce mullion (audio) \

Definition of mullion

: a slender vertical member that forms a division between units of a window, door, or screen or is used decoratively

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Other Words from mullion

mullion transitive verb

Examples of mullion in a Sentence

Recent Examples on the Web Mies made the mullions in the same I-beam shape as the steel structure inside the building. Michael Kimmelman, New York Times, "The Hidden Feats That Built New York’s Towering Skyscrapers," 29 Apr. 2020 Nonetheless, Hancock’s board, determined to avoid future embarrassments, decided that as the building was repaired, each large sheet of glass should be replaced by three smaller panels, separated by mullions. Fred A. Bernstein, New York Times, "Henry Cobb, Courtly Architect of Boston’s Hancock Tower, Dies at 93," 4 Mar. 2020 The paneled wood walls and lack of trim are modern touches, as is the floor-to-ceiling window, but the small panes and mullions are traditional. Mimi Read, House Beautiful, "Ruard Veltman on Blending Modernism and Traditional Style," 2 Jan. 2013 Black window mullions and door and chair frames add graphic punch in a family vacation home on Sullivan's Island, South Carolina. Sarah Yang, House Beautiful, "Top Pin of the Day: A Beachy Dining Room," 2 June 2014 There are a variety of code violations with the most costly being a mullion that needs to be replaced on a door. Evan Frank, Milwaukee Journal Sentinel, "No liquor license for Olympia Resort until new owners make repairs, officials say," 25 June 2018 Also think about making a statement with glass cabinet doors – traditional styles usually feature mullions, while contemporary do not. Michelle Martin For Toll Brothers, Detroit Free Press, "Top 6 trends in the kitchen and bath," 16 May 2018 The kitchen opens to a large breakfast room where glasses and dishes are displayed in a built-in hutch with glass mullion doors. Karen A. Avitabile,, "Property of the Week: 56 Old Stone Crossing, West Hartford," 3 Aug. 2017 The Monroe house is painted in a warm terracotta color, with olive trim and front-step metal railings (added by the current owners) that echo the angular window mullions. Steve Bennett, San Antonio Express-News, "2 Beacon Hills homes came from 1904 St. Louis World’s Fair," 29 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mullion.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of mullion

1567, in the meaning defined above

History and Etymology for mullion

probably alteration of monial mullion

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Time Traveler for mullion

Time Traveler

The first known use of mullion was in 1567

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Cite this Entry

“Mullion.” Dictionary, Merriam-Webster, Accessed 7 Aug. 2020.

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More Definitions for mullion


How to pronounce mullion (audio)

English Language Learners Definition of mullion

: an upright piece of wood, stone, metal, etc., that separates two windows

More from Merriam-Webster on mullion

Rhyming Dictionary: Words that rhyme with mullion Encyclopedia article about mullion

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