Rustin

Transferred use of the surname Rustin.

However, in the present-day English-speaking world, Rustin as a given name can also be a combination of two existing names. For example, it is not inconceivable that there have been parents who decided to blend a name starting with R- (such as Ronald) with either Dustin or Justin. In some cases, Rustin may even be a variant form of Rusty.

Hypocorism of Rustique.

It is a Persian/Farsi name meaning genuine, true or honest. The word is the combination of "Rust"+"in" where "Rust" means true/genuine and "in" is emphasizing on the adjective, here Rust.For example "Rustin friend" is referring to a genuine friend who would help and support you in any condition.