From progressive +‎ -ism.

• (Received Pronunciation) IPA^(key): /prəˈɡrɛsᵻvɪz(ə)m/

• Audio (Southern England):

  (file)

• (General American, Canada) IPA^(key): /prəˈɡrɛsɪˌvɪzəm/, /proʊˈɡrɛsɪˌvɪzəm/

progressivism (usually uncountable, plural progressivisms)

1. A political ideology that favours progress towards better conditions in society.
   • 1976 July 2, John Rockwell, “The Pop Life”, in The New York Times‎^[1]:

     In New York the range of influences is as diverse as anywhere else, even if there unquestionably is a tendency toward Velvet Undergroundish punk rock and British progressivisms.

   • 2017 April 7, Matthew Penza, “The Problem with the Big Tent”, in The Princeton Tory‎^[2]:

     By adopting big-tentism, conservatism has been allowed to degenerate into pseudo-conservatism, an ideology essentially the same as contemporary progressivism: embracing of every ideology and policy position whose inclusion is politically expedient.

   • 2023 November 16, Pamela Paul, “Progressives Aren’t Liberal”, in The New York Times‎^[3]:

     Some aspects of contemporary progressivism look less like actual progress and more like a step in reverse.