A term used to refer to Engineered wood products typically plywood. Sheetgoods, in the U.S. normally come in 4'X8' Sheets.
The term sheetgoods can also refer to products of other materials such as drywall/sheet-rock (gypsum and paper), Coroplast (plastic), Lexan, PlexiGlas.
Other types of sheet goods;
MDF- medium density fiberboard
OSB- Oriented Strand Board < often called "chip board" >
MDO- Medium Density Overlay
Luan- Actually a 3 or 4 ply plywood but deserves recognition.
Masonite- also referred to as Tempered Hardboard < note Masonite and MDF are not the same material>