* An acronym for a specific organization, group, or project. To know what it stands for, you'd need more context.
* A misspelling of a different word or acronym. Check if there are any similar-looking words or acronyms that might be intended.
* An abbreviation used in a particular field or industry. If you can tell me the context where you saw "TATMR", I might be able to help.
Please provide more information so I can understand what "TATMR" might stand for.