0 a person who believes in acting independently, without involving another group or country:
He is a left-winger and apparently still a committed unilateralist.
1 of or relating to unilateralism (= the process or fact of deciding a policy or action without involving another group or country):
There's a return to a more unilateralist worldview.
He has aggressively criticized the president for his unilateralist approach to the world.
We're accused of not consulting, of being unilateralists.
the recent defeat of the unilateralists on nuclear disarmament
We are working closely with our allies so we are not perceived as unilateralist cowboys.
