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n. A vertical member, as of stone or wood, dividing a window or other opening.

n. A vertical bar between the panes of glass or casements of a window or the panels of a screen.

n. A slender bar or pier which forms the division between the lights of windows, screens, etc.

n. An upright member of a framing. See stile.

v. To furnish with mullions; to divide by mullions.

n. In architecture:

n. One of the divisions between panels in wainscoting. Formerly monial.

To form into divisions by the use of mullions.

n. a nonstructural vertical strip between the casements or panes of a window (or the panels of a screen)

"There are large "alfices" (rectangular ornamentation in the façade) enhancing the entrance, windows with small open spaces, separated by a small column-like mullion and multiple arches similar to the architecture found in Granada, Spain."

mullioned    mullions   

slip    strip   

stile   

mullioned   

munnion    monial   

herse    tolaunch    they'llride    radioisotope    two-bar    inditing    mantlepiece    ink-jet    guardroom    gas-fired