Phobia means fear.
A phobia is an irrational fear phobia phobic means the fear of fear itself
Your question asks what the phobia of a fear is (X-phobia-phobia): the PHOBIA OF THE FEAR of the number eight would be octophobia-phobia. The fear of the number eight would simply be octophobia.
If failing is your fear the name for the failing phobia (phobia mean fear) is atychiphobia.
To have a phobia is to have a fear.
perichoraphobia. perichora (suburbs) + phobia (fear)
Turophobia - fear/phobia of cheese.
Bebuphobia...that is the fear or phobia of blueberries.
Atychiphobia (kakorrhaphiophobia, fear of failure, fear of failing, failure phobia).
Mud Phobia is the phobia (fear) of mud. Its called mysophobia, myso meaning mud and phobia meaning fear.
Theophobia- the irrational fear of a god or deity. Remember its only a phobia if its an "irrational" fear, a normal healthy fear is not a phobia.