from The Century Dictionary and Cyclopedia
- n. A roof having (as seen from within) the general shape of a cradle-vault, wagon-vault, or tunnel-vault: always a construction of light materials, not of masonry. It is usually built with wooden ribs bent or cut to the curve and boarded up.
Sorry, no etymologies found.
An almost perfect cradle-roof, tunnel-like from end to end of the long central aisle, adds by its simplicity of form to the magnificent unity of effect.