Webster's 1828 Dictionary
BUTMENT
n. 1. A buttress of an arch; the supporter, or that part which joins it to the upright pier.
2. The mass of stone or solid work at the end of a bridge, by which the extreme arches are sustained. The mass of stone at the end of a timber bridge, without arches, is called by the same name. It is written also abutment.
Webster's 1913 Dictionary
BUTMENT
But "ment, n. Etym: [Abbreviation of Abutment. ]
1. (Arch. )
Defn: A buttress of an arch; the supporter, or that part which joins it to the upright pier.
2. (Masonry )
Defn: The mass of stone or solid work at the end of a bridge, by which the extreme arches are sustained, or by which the end of a bridge without arches is supported. Butment cheek (Carp. ), the part of a mortised timber surrounding the mortise, and against which the shoulders of the tenon bear. Knight.