the.com/mansard

means A roof design with two slopes on each side, the lower one steep and the upper one almost flat, which tucks extra usable floors inside what looks from outside like just a roofline.

from Named after François Mansart, a 17th-century French architect who popularized the style (his nephew Jules Hardouin-Mansart later spread it further through grand French buildings). The roof lets you squeeze a full habitable story into the attic without raising the building's visible height — handy in cities like Paris, where height limits and taxes were once calculated to the roofline. The spelling drifted over time from 'Mansart' to 'mansard,' as the man's name settled into the language as a plain architectural term.