Hubris
Hubris (, also hybris, from ancient Greek ὕβρις) refers to a purely negative emotion that may be defined verbally in a modern context as extreme or foolish pride or confidence. In its ancient Greek context, it typically describes violent behavior rather than an attitude. The adjectival form of the noun hubris is "hubristic".
Hubris is usually perceived as a characteristic of an individual rather than a group, although the group the offender belongs to may unintentionally suffer consequences from the wrongful act. Hubris often indicates a loss of contact with reality and an overestimation of one's own competence, accomplishments or capabilities.