The Sai

Sai (釵) is the Ryukyu name for a traditional Okinawan weapon also used in India, China, Indonesia, Malaysia and Thailand. Its basic form is that of a pointed, rod-shaped baton, with two long, unsharpened projections (tsuba) attached to the handle. The very end of the handle is called the knuckle. Sai are constructed in a variety of forms. Traditional sai are round, while some reproductions have adapted an octagonal middle prong.

It is believed the sai was always a weapon. Although, some hypothesize it originated as an agricultural tool used to measure stalks, plow fields, plant rice, or to hold cart wheels in place, though the evidence for this is limited. The sai is known to have been used in other parts of Asia before its arrival on Okinawa. It is also of note that the Greek letter psi, is a homonym of sai and that the shape of the letter itself closely resembles the shape of the weapon.