Sommer, in architecture, a girder or main beam of a floor; if supported on two storey posts and open below, it is called a bress or breast-summer. The word is also spelled "summer," and is the same as "Sumpter," a pack-horse, Fr. sommier, O. Fr., saume, from Low Lat. salma, pack, burden, Gr. afirypa, aaTTECV, to fasten a pack on a horse.