: It may be a "password" or "paper" (slang in some circles for the decryption key or source info) for a specific private release.
If you are looking for a or a specific source for this file, it is typically found on the original website, forum thread, or Telegram channel where the link was first posted. Search results for "OPODODI" on general archives like Internet Archive currently only return unrelated scans of ancient Latin medical texts.
: Often used in file-sharing communities (like forums or Usenet) as a randomized or obfuscated name to prevent automated copyright takedowns.
: The suffix .part04.rar indicates this is the fourth segment of a larger split archive. You will likely need all parts (part01, part02, etc.) to successfully extract the contents.