We don't have synonyms for butment yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are abutment and hutment.
(n) :
(masonry) 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.
(n) :
(architecture) A buttress of an arch; the supporter, or that part which joins it to the upright pier.
(n) :
(masonry) 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.
(n) :
(architecture) A buttress of an arch; the supporter, or that part which joins it to the upright pier.