Alchemy or a sign/mark
In Arabic, the name refers to the ancient practice of alchemy or the study of signs and symbols. It is often associated with transformation and hidden knowledge. In some contexts, it can also be interpreted as a variation of names meaning 'sign' or 'mark'.
Less common today
Simya isn't in the latest US Top 1000. It last peaked at #5,694 in 2006.
US births per 5-year period, 1990βpresent (SSA data).