What is the phobia for rejection called?

Kakarrhaphiophobia-fear of failure or defeat, you could say rejection if you would like. here's advice from your neighborhood friendly Immortal ninja!

Try this: You might not think of fear of rejection as a phobia, but if the thought of being rejected causes such anxiety that you can not participate in a relationship, then it is considered to be a phobia. Phobias are rooted often in something that happened to us as children, usually at an age so young that we were unable to voice our fear. This leaves a psychological imprint which prevents us from experiencing situations like or that remind us of the initial imprinted condition without having something akin to an anxiety attack. For instance, if a parent abandoned you before you were old enough to talk about it, this may leave a subconscious imprint which causes you to not be able to form a lasting bond with another person; a phobia.

It's not a phobia. It has to do with self esteem.

well, its not really a phobia, cause it isnt as widely experienced as other phobias