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

Other Words from mullion

mullion transitive verb

Examples of mullion in a Sentence

Recent Examples on the Web Architectural details include eyebrow dormer windows, two-story columns and spiderweb mullion windows, according to Ms. Seery. Sarah Paynter, WSJ, 10 Mar. 2022 Then, spread glue in the back rail mortises and on the mullion tenons. Darren Orf, Popular Mechanics, 8 Aug. 2020 Mark the locations of the mullion mortises in the back rails and rout them with a 3/8-in. Darren Orf, Popular Mechanics, 8 Aug. 2020 Mies made the mullions in the same I-beam shape as the steel structure inside the building. Michael Kimmelman, New York Times, 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, 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, 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, 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, 25 June 2018 See More

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.

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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The first known use of mullion was in 1567

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Cite this Entry

“Mullion.” Dictionary, Merriam-Webster, Accessed 3 Oct. 2022.

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