Refers to the video resolution, which is High Definition (HD).
The specific string provided— thank-you-2022-hq-hindi-dubbed-720p-www-7starhd-autos-mkv —is a typical naming convention used by third-party file-sharing websites. The title and release year of the film. thank-you-2022-hq-hindi-dubbed-720p-www-7starhd-autos-mkv
This is a "watermark" or tag identifying the third-party website from which the file originated. Refers to the video resolution, which is High