melting pot

noun

1. a pot in which metals or other substances are melted or fused.
2. a country, locality, or situation in which cultural assimilation results in blending the heritage and traditions of previously distinct ethnic groups.

noun

1. a pot in which metals or other substances are melted, esp in order to mix them
2. an area in which many races, ideas, etc, are mixed

A term expressing the view that immigrants to the United States have been fused or melted into a single people.