What is "shemr"

Shimr bin Ziljoshan or Shimr ( Arabic: شمر ابن ذی الجوشن) was a son of Ziljoshan from the tribe of Banu Kelaab, one of Arabia's tribes. Umm ul-Banin, the mother of Abbas ibn Ali, was also from the Banu Kelaab tribe. Shimr has a villainous reputation in Shia Islam. He is known as the man who killed Islamic prophet Muhammad's grandson Hussein ibn Ali at the Battle of Karbala. Shia traditions relate that Shimr was eventually killed by Mukhtar al-Thaqafi's troops who wished to take revenge upon Husayn and his family's killers. His body was then torn to pieces by wild dogs.

Shimr is depicted in the passion plays during the Shia mourning remembrance of Ashura.