Pull request (PR): A standardized request to merge a piece of code into a repository's main branch, such as a Pull Request on GitHub or a Merge Request on GitLab
Contributor: Someone submitting pull requests and/or committing to a repository
Code owner: A contributor with administrative rights on the code repository or explicitly defined as such in the repository
PR owner: A contributor responsible for managing and merging a PR, usually the contributor submitting the PR, but can be changed by explicit assignment