Add Linux server to AD without entering password

When I run command:

realm join -U adminuser@PORTON.COM.IL porton.com.il --verbose 

I am prompted to enter the password for adminuser@PORTON.COM.IL. Since I want to run this in a script for a lot of servers, Is there a way to skip this prompt or automatically send the password from the script (Its script running in bash or csh).