We don't have synonyms for gomai yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are goman, goma and gofai.
(n) :
(uncountable) A construction method for Japanese-style blade steels, composed of 5 layers of 3 steels, with a core, sandwiched by another steel, sandwiched again by another steel. The sandwiching may be two sheets, or traditionally one sheet folded over as a taco.
(n) :
(countable) A steel sandwich made by this method, before and after being welded.
(n) :
(uncountable) A construction method for Japanese-style blade steels, composed of 5 layers of 3 steels, with a core, sandwiched by another steel, sandwiched again by another steel. The sandwiching may be two sheets, or traditionally one sheet folded over as a taco.
(n) :
(countable) A steel sandwich made by this method, before and after being welded.