Randori

is a term used in Japanese martial arts to describe free-style practice (sparring). The term denotes an exercise in 取り tori, applying technique to a random ( 乱 ran) succession of uke attacks.

The actual connotation of randori depends on the martial art it is used in. In judo, jujutsu, and Shodokan aikido, among others, it most often refers to one-on-one sparring where partners attempt to resist and counter each other's techniques. In other styles of aikido, in particular Aikikai, it refers to a form of practice in which a designated aikidoka defends against multiple attackers in quick succession without knowing how they will attack or in what order.