Cock-Blocker Designate. A person, usually a close friend, who has been assigned the task at a specific social event of preserving another's
chastity and/or self-respect when that person has announced that they do not feel up to the task themselves. This normally involves preventing the person from hooking up or
macking a
potential sexual partner who is not up to the ideal.
"
Yo, I can't drink too much tonight. Sue's tempted to move on that
guy who works at
Bucky's and she needs me to be CBD."