What is the word origin for trans?

The word "trans" is derived from the Latin word "transīre", which means "to go across" or "to pass over". It has been used in English since the 14th century to mean "across", "beyond", or "on the other side of". In the 19th century, it began to be used in a medical context to refer to individuals whose gender identity does not match the sex they were assigned at birth.