There are not synonymous, actually the diference is quite
simple: Sudamérica: Geographically, a subcontinent of "América",
limited to the north by the Caribean sea. It does not include
the Caribean, Central America ("Centroamérica") or North America
("Norteamérica"). Argentina, Brazil and Suriname are in
"Sudamérica", but not Costa Rica, México or Cuba. Latinoamérica:
All american countries where a romance language (Spanish,
Portuguese, French) is spoken as main language. Includes
countries of South, North, Central America and the Caribean.
Argentina, Brazil, Costa Rica, México and Cuba are in
"Latinoamérica", but not Suriname. Particularly, Canada as
country is not included despite French is spoken in some
provinces. Hispanoamérica: All american countries where Spanish
is spoken as main language. Includes countries of South, North,
Central America and the Caribean. Argentina, Costa Rica, México
and Cuba are in "Hispanoamérica" but not Brazil or Suriname.
It's important to remark that there is no term to refe