Avijjasava

Canker of ignorance; ignorance of the way things are; One of the four Asavas; intoxication of ignorance (avijjasava)

avijjasava, lack of understanding on the fundamental level, (such as not understanding the nature of life, aging and death and how they should be related to), aging and death cause the unenlightened being to experience fear, melancholy, despair and superstitious grasping.