We don't have synonyms for matchboard yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are patchboard, notchboard and archboard.
(n) :
(carpentry) A type of wooden board that connects with others using a tongue and groove system
(n) :
(sand casting) A thin piece of material (such as wood, plaster, or metal) that forms and aligns the matched parting surfaces for the two parts (the cope and the drag) of a molding box or flask, to which board patterns are attached in some casting methods.
(n) :
(carpentry) A type of wooden board that connects with others using a tongue and groove system
(n) :
(sand casting) A thin piece of material (such as wood, plaster, or metal) that forms and aligns the matched parting surfaces for the two parts (the cope and the drag) of a molding box or flask, to which board patterns are attached in some casting methods.