arm·lock 
(ärmlŏk′)
(ärmlŏk′)n.
A hold in wrestling and martial arts in which the opponent's arm is immobilized, often by flexing or extending the opponent's elbow or shoulder joint.
armlockSofia Mattsson of Sweden (red) and Clarissa Chun of the US (blue) competing in the Women's Freestyle Wrestling at the 2008 Olympic Games
Beijing, China