In Greek mythology

Greek mythology

Greek mythology is the body of myths and legends belonging to the ancient Greeks, concerning their gods and heroes, the nature of the world, and the origins and significance of their own cult and ritual practices. They were a part of religion in ancient Greece...

, Thrasos (Greek Θράσος n.) is the personified concept of boldness.

Although the word θράσος itself could be used both in the positive ("courage") and the negative ("over-boldness, insolence") senses, in the only context where Thrasos appears as a personification (a daemon), it is definitely a malicious being, mentioned together with Hybris

Hubris

Hubris , also hybris, means extreme haughtiness, pride or arrogance. Hubris often indicates a loss of contact with reality and an overestimation of one's own competence or capabilities, especially when the person exhibiting it is in a position of power....

 and Atë

Ate

Atë or Aite a Greek word for "ruin, folly, delusion", is the action performed by the hero, usually because of hubris, that leads to his or her death or downfall. There is also a goddess by that name in Greek mythology, a personification of the same.In Homer's Iliad she is called eldest daughter...

 and opposed to Dike

Dike (mythology)

In ancient Greek culture, Dikē was the spirit of moral order and fair judgement based on immemorial custom, in the sense of socially enforced norms and conventional rules. According to Hesiod In ancient Greek culture, Dikē (Greek: Δίκη, English translation: "justice") was the spirit of moral...

.