means A raised, flat outdoor platform or level area — whether a paved patio beside a house, a row of houses on a step of ground, or one of a series of horizontal steps cut into a slope.

from From Old French 'terrasse,' a platform or pile of earth, by way of Vulgar Latin 'terracea,' meaning an earthen embankment — itself rooted in Latin 'terra,' earth. The same 'terra' that grows in territory, terrain, and terracotta (literally 'cooked earth'). So a terrace is, at heart, just shaped ground — a bit of the earth flattened and propped up to be stood upon.