›to state an opinion or claim a right forcefully: [+ that clause]The companies have asserted that everything they did was appropriate.›To assert is also to behave in a way that shows power, authority, or control: Several members of Congress called upon the president to assert leadership.›If you assert yourself, you act forcefully in a way that expresses your confidence: You have to learn to speak up and assert yourself at meetings, or you’ll never get anywhere.assertion
/əˈsɜr·ʃən/n[C]›Critics say the company forces workers to drive recklessly, an assertion the company denies.