Difference between merchandise trade and trade in goods? What is the difference between merchandise trade and trade in goods? Are they the same? If so, would total trade be just trade in goods + trade in services, aka merchandise trade + trade in services?
As far as I understand merchandise trade and trade in goods are the same.

The IMF Balance of Payments Manual breaks down international transactions according to standard categories. Trade is one of these categories. Trade is defined as international transactions involving products, i.e. exports and imports of goods (or merchandises) and services. 


Merchandise or good trade are transactions involving the transfer of ownership of a tangible and moveable object from a seller to a buyer.
Services are transactions in which a consumer benefits from actions taken
by the service provider.


There is a subtle sub-category, which is 


Goods for processing that are transactions in which raw goods (e.g. cotton thread) from country A are exported to country B, where
they undergo processing, and are then imported back into country A (e.g. t-shirts) without a transfer of ownership.