Hypercritical means overcritical or excessively critical: “The hypercritical nature of his father discouraged him to such an extent that he left the idea of becoming a musician.”
Hypocritical , on the other hand , means pretending to have certain beliefs about what is proper or right, but practicing the opposite or contrary behavior of those beliefs: “It is hard to find a genuine religious leader these days, most of them are hypocritical.”
