What does theta chi's secret word 'Sisturus' mean?

If you don't know meaning then you do not need this answer it is a part of Theta Chi and to it's members only please just respect that of our organization.

Please do not reveal the secrets of any fraternity. If you learn one by accident, keep it to yourself, or tell a brother of that fraternity that you heard it from so-and-so. If you really wish to know, maybe joining the organization would be the best bet.