Muntin
ahd-5
noun.
A strip of wood or metal separating and holding panes of glass in a window.
noun.
A vertical framing member set between two rails in a door or in paneling.
The Century Dictionary and Cyclopedia
noun.
The central vertical piece that divides the panels of a door.
the GNU version of the Collaborative International Dictionary of English
noun.
Same as
mullion
; -- especially used in joiner's work.
Wiktionary, Creative Commons Attribution/Share-Alike License
noun.
One of the
separators
between
panes
of
glass
in a
composite
window
.
Word Usage
"The "muntin" is the upright between the two stiles."
Equivalent
munting
variant
mullion