isolationist

UK: /ˌaɪsəˈleɪʃ^ənɪst/ US: (ī′sə lā′shə nist, is′ə-)

WordReference Random House Unabridged Dictionary of American English © 2025

i•so•la•tion•ist  (ī′sə lā′shə nist, is′ə-), n. 

1. a person who favors or works for isolationism.

adj. 

2. of, pertaining to, or characteristic of isolationists or isolationism:
   to be accused of isolationist sympathies.

• isolation + -ist 1860–65, American.

WordReference Random House Learner's Dictionary of American English © 2025

i•so•la•tion•ism /ˌaɪsəˈleɪʃəˌnɪzəm/   n. 

[uncountable]
1. Government the policy or doctrine that calls for isolating one's country from alliances with and commitments to other countries.

i•so•la•tion•ist, n. [countable] , adj. 

WordReference Random House Unabridged Dictionary of American English © 2025

i•so•la•tion•ism  (ī′sə lā′shə niz′əm, is′ə-), n. 

1. Government the policy or doctrine of isolating one's country from the affairs of other nations by declining to enter into alliances, foreign economic commitments, international agreements, etc., seeking to devote the entire efforts of one's country to its own advancement and remain at peace by avoiding foreign entanglements and responsibilities.

• isolation + -ism 1920–25, American.