mullion
/ˈmʌliən/noun, verb
mullion is a noun meaning “A vertical bar between the panes of glass or casements of a window or the panels of a screen” (English Wiktionary, September 2026). It is spelled M-U-L-L-I-O-N, and it appears about once in every 13 million words in written English (wordfreq, 2021 data). The plural of mullion is mullions.
What does mullion mean?
noun
- 1
A vertical bar between the panes of glass or casements of a window or the panels of a screen.
verb
- 1
To shape into divisions by means of mullions.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
How do you pronounce mullion?
- /ˈmʌliən/
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
Forms of mullion
- mullions plural, present, singular, he/she/it
- mullioning participle, present
- mullioned participle, past
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
How common is mullion?
Mullion appears about once in every 13 million words in written English, the 109,062nd most frequent word form in the list.
Source: written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
Mullion in Spanish, French, German and Portuguese
In the sense vertical bar between the casements of a window:
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Translations are Wiktionary's, by sense; a linked word has its own PlainSpell page.
Where does mullion come from?
Alteration of monial (“mullion”), or metathesis of Middle English moyniel, both ultimately from Old French moinel.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).