atomsm
The term "atomsm" does not correspond to any recognized scientific, technical, or commonly used concept. It is possible that this is a misspelling of a related term, or a neologism that has not yet gained widespread recognition.
If the intended term was "atoms," then this refers to the basic unit of a chemical element.
Alternatively, if "atomsm" was intended to relate to a specific project, software, or concept, further clarification