assert

To declare with assurance or plainly and strongly; to state positively.

Numerous experimental tests and other observations have been offered in favor of animal mind reading, and although many scientists are skeptical, others assert that humans are not the only species capable of representing what others do and don’t perceive and know.

He would often assert that there was life on other planets.

To use or exercise and thereby prove the existence of.

to assert one's authority

Salman Rushdie has asserted his right to be identified as the author of this work.

To maintain or defend, as a cause or a claim, by words or measures; to vindicate a claim or title to.

to assert our rights and liberties

To insist on the legitimacy of one's rights, opinion, etc; not to allow oneself to be dismissed; to ensure that one is taken into consideration; to make oneself respected; to be assertive. See assert oneself.

Since going to therapy, I've found it much easier to assert myself.

To declare that a condition or expression must be true at a certain point in the source code (in some cases causing the program to fail if it is not, as a safeguard).

Synonym of assertion.