sub·​frame ˈsəb-ˌfrām How to pronounce subframe (audio)
variants or sub-frame
plural subframes or sub-frames
: a secondary frame
especially : one that is used for the attachment and support of a finish frame (as of a door or window) or of finish panels (as of a wall)
Strictly speaking, the vertical members of a curtain wall's subframe are called mullions, while horizontal members are called transoms. Jason Alread et al.
The rolled steel sections, generally 1/8" thick and 1 - 1 1/2" wide, were used for all the components of the windows: sash, frame, and subframe The Preservation of Historic Architecture: The U.S. Government's Official Guidelines for Preserving Historic Homes

Word History

First Known Use

1866, in the meaning defined above

Time Traveler
The first known use of subframe was in 1866

Dictionary Entries Near subframe

Cite this Entry

“Subframe.” Dictionary, Merriam-Webster, Accessed 7 Dec. 2022.

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