The bichaq is a single-edged dagger of Turkish origin, widespread in areas controlled by the Ottoman Empire and its close neighbors. The blade of this knife is either straight, holds a slight forward curve, like a short yataghan, or very rarely a backwards curve, like a jambiya. The hilt, often made of precious materials, is reminiscent of a modern-day butter-knife.

This name is also used to denote a type of highly curved sword of the Laz people of coastal Georgia and Turkey similar to the yataghan, which is treated on this wiki as the Laz bıçağı.

Related weapons include the kard and the kindjal.