It's commonly used to refer to MDA, although generally a miconception. Sassafras is sometimes used for the contained safrole as a precursor to create MDMA. I believe (?) that the human body also converts safrole to MDA. Hence the misconception.
Either way, MDA is like incredibly hallucinogenic and psychedelic MDMA. Imagine a high dose of MDMA but way more intense. Very visual. Very fun.
But what you have is possibly not actually MDA. I say this not as a general precaution, but based on the modesty of the reported effects that I've seen from those who have tried these new European batches. It has been a very rare substance in recent years, which has resurfaced on the DW. But I've yet to see any tested.