Definition of Progressive Party in US English:

Progressive Party

proper noun

  • Any of three related political parties active in the first half of the twentieth century that favored social reform. The most prominent was that formed under Theodore Roosevelt in 1912.

    • ‘Increasingly critical of President Truman's foreign policy, in 1948 he ran for president as a Progressive Party candidate.’
    • ‘Back in 1912, Theodore Roosevelt ran on the Progressive Party ticket.’