a. A sheet of glass or other transparent material set into a window or door.
b. A framed section of a window or door that holds such a sheet.
2. A panel, as of a door or wall.
3. One of the flat surfaces or facets of an object, such as a bolt, having many sides.
[Middle English, section, pane of glass, from Old French pan, piece of cloth, panel, from Latin pannus, cloth; see pan- in the Appendix of Indo-European roots.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.