To avow something means to declare it openly and firmly, often when others might doubt you or when it takes courage to speak up. When you avow your beliefs, you state them clearly and publicly for everyone to hear.

The word carries a sense of boldness and conviction. A scientist might avow her confidence in a controversial theory even when other researchers disagree. A character in a story might avow his loyalty to a friend who's been accused of something. When you avow something, you're taking a stand and making your position unmistakable.

If someone asks whether you support a particular idea and you avow that you do, you're declaring your support in a way that others can count on, showing genuine commitment.

The opposite is disavow, which means to deny any connection with something or to refuse to acknowledge it. A person might disavow an old opinion they no longer hold.