Pan-American Congress \Pan-American Congress\ Any of several meetings of delegates from various American states; esp.: (a) One held in 1889-90 in the United States, at which all the independent states except Santo Domingo were represented and of which the practical result was the establishment of the Bureau of American Republics for the promotion of trade relations. (b) One held in Mexico in 1901-1902. (c) One held at Rio de Janeiro in 1906.