Transom most commonly refers to a horizontal crosspiece above a door or window. It can separate the main opening from a smaller window above it. By extension, that upper window is also called a transom or transom window. Such windows may admit light, improve ventilation, or add a decorative feature without changing the main doorway.
In boating, the word names the surface across the stern, or back, of a vessel. On many small motorboats, the outboard motor attaches to this part. Although the architectural and nautical uses describe different objects, both retain the basic idea of something extending across an opening or end.
The phrase over the transom has a figurative meaning, especially in publishing. A manuscript sent over the transom arrives without being requested or introduced by an agent. The image is of papers being passed or tossed through the small opening above an office door. Today, the expression can apply more broadly to unsolicited proposals, applications, or other material.
- Morning light came through the transom above the front door.
- The mechanic reinforced the transom before mounting the motor.
- The magazine accepts a few stories over the transom each year.
Context usually makes the intended sense clear. Doors and windows suggest the architectural meaning, boats suggest the stern structure, and publishing or submissions suggest the figurative expression.