Protestantism

UK: /ˈprɒtɪstəntɪzəm/ US: (prot′ə stən tiz′əm)

WordReference Random House Unabridged Dictionary of American English © 2026

Prot•es•tant•ism  (prot′ə stən tiz′əm), n. 

1. Religion the religion of Protestants.
2. Religion the Protestant churches collectively.
3. Religion adherence to Protestant principles.

• Protestant + -ism 1640–50

Collins Concise English Dictionary © HarperCollins Publishers::

Protestantism / ˈprɒtɪstənˌtɪzəm/ noun

1. the religion or religious system of any of the Churches of Western Christendom that are separated from the Roman Catholic Church and adhere substantially to principles established by Luther, Calvin, etc, in the Reformation

WordReference Random House Learner's Dictionary of American English © 2026

Prot•es•tant /ˈprɑtəstənt/   n. [countable]

1. Religion any Western Christian not a follower of the Roman Catholic Church.

adj. 

2. Religion of, relating to, or belonging to Protestants or their religion:
   a Protestant hymnal.

Prot•es•tant•ism, n. [uncountable] See -test-.

WordReference Random House Unabridged Dictionary of American English © 2026

Prot•es•tant  (prot′ə stənt or, for 4, 6, prə tes′tənt), n. 

1. Religion any Western Christian who is not an adherent of a Catholic, Anglican, or Eastern Church.
2. Religion an adherent of any of those Christian bodies that separated from the Church of Rome during the Reformation, or of any group descended from them.
3. Religion (originally) any of the German princes who protested against the decision of the Diet of Speyer in 1529, which had denounced the Reformation.
4. (l.c.) a person who protests.

adj. 

5. Religion belonging or pertaining to Protestants or their religion.
6. (l.c.) protesting.

• German or French, for Latin prōtestantēs, plural of present participle of prōtestārī to bear public witness. See protest, -ant
• 1530–40