All over the world, Koskan (Koskan 
) is an extremely rare unknown gender first name. Much more frequently, Koskan is the last name as well as the forename.
Mr, Devin, Debra, Danie, Donna, Larry, Lexie, James, Tracy, Verna, Fatih, Irene, Alexis, Pamela, Robert, Ronald, Dilsah, Joshua, Nicole, Michael, Shannon, Carolyn, Perla, Keith, Karen, Brett, Pam, Ron, Joy, Efe, Mary, Mike, Sean, Paul, Ryan, Levi, Cynthia, Lisa, John, Joel, Elif, Erin, Umit, Maria, Sally, Allen, Ahmet, Cindy, Luke, and Kaitlin