What is Latin sidus?

Excuse me, could you please clarify what is meant by "Latin sidus"? I'm not familiar with this term in the context of Latin language or cryptography. Is it a specific word or phrase with a particular meaning in ancient texts or modern usage? Additionally, I'm curious if this term has any relevance to the world of cryptocurrency or finance, as my expertise lies in those fields. Any insight you could provide would be greatly appreciated.