A vertical member, as of stone or wood, dividing a window or other opening.
[Alteration of Middle English moniel, from Anglo-Norman moynel, perhaps from moienel, middle, from moien, from Latin mediānus, from medius; see medhyo- in the Appendix of Indo-European roots.]
mullioned (mŭlyənd) adj.
(click for a larger image)mullion
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