Mullion

usgb/ˈmʌliən/
noun

A vertical bar between the panes of glass in a window.

The mullion in the middle of the window divided it into two sections.
Visual representation of "mullion" - A vertical bar between the panes of glass in a window.

Often appears as...

  • window mullion
  • mullion bar

Usage tips

Technical

Definition 1 of 2
Visual representation of "mullion"
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Architectural Feature

Used to describe parts of a building's windows, not just any vertical bar.

Illustration for Architectural Feature
The modern office building's facade was notable for its glass walls and slim mullions.
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Visual Separation

Mullions visually break up large glass areas, making windows more interesting.

Illustration for Visual Separation
The designer added mullions to create a pattern on the vast glass surface.
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Supportive Role

Mullions can also provide structural support to windows.

Illustration for Supportive Role
To prevent the large window from sagging, they reinforced it with a sturdy mullion.
Visual representation of the word "Mullion"

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