A pinnacle (from Latinpinnaculum, a little feather, pinna, compare panache) is an architectural ornament originally forming the cap or crown of a buttress or small turret, but afterwards used on at the corners of and in many other situations. The pinnacle looks like a small spire. It was mainly used in Gothic architecture.
Flat, or flatness, describes an object or condition that is very smooth or level.In Great Britain, Ireland and Australia, as well as in English spoken in Commonwealth countries such as India, a "flat" means an apartment.