Cruciatus Curse

Cruciatus Curse also known as the Torture Curse, this curse is one of the Unforgivable Curses and is known to be one of the darkest, most sinister spells known to Wizardkind. Causes intense, agonizing pain when cast successfully. The incantation for the curse is “crucio.”

Cru·cia·tus Curse
/kro͞o’sē’at’əs kərs/
noun

Cruciatus Curse History
Created in the early Middle Ages by dark witches or wizards, the Cruciatus Curse was initially made for torture, though was an effective tool in duels as well. The curse was very popular for a time, but in 1717, the Unforgivable Curses were made illegal, and the use of the curses would land the perpetrator a life sentence in Azkaban. Though mainly used by Dark wizards and witches, during the First Wizarding War, the Department of Magical Law Enforcement, headed by Bartemius Crouch Senior, legalised the use of the Unforgivable Curses against those suspected of being Death Eaters until the First Wizarding War ended. The most well-known victims of the Cruciatus Curse are Frank and Alice Longbottom, former Aurors, who were tortured until they lost their minds by Death Eaters. The Unforgivable Curses were legalised once more during the Second Wizarding War, when He-Who-Must-Not-Be-Named took over the Ministry of Magic, though this legalization allowed all witches and wizards to use the curses.

Cruciatus Curse Etymology 
The incantation “crucio” translates to “I torture,” and “cruciatus” comes from the Latin and can be translated as either “pain” or “torture.”