The Balance of Payments and International Investment Position Manual Sixth edition states that:
10.7 Goods are physical, produced items over which ownership rights can be establised and whose economic ownership can be passed from one institutional unit to another by engaging in transactions. They may be used to satisfy the needs or wants of households or the community or used to produce other goods or services. The production of a good can be separated from its subsequent sale or resale. Goods are shown separately from services.
Goods and Services Account
Goods under merchanting
Valuation of transactions and other flows (link not yet available)