Complex sentence: To qualify as an ōdachi the sword in question must have a blade length of 3 shaku (90.9 cm) or more, however, as with most terms in Japanese sword arts, there is no exact definition of the size of an ōdachi.
Split into simpler sentences: To qualify as an ōdachi, the sword in question must have a blade length of 3 "shaku" (90.9 cm) or more. However, as with most terms in Japanese sword arts, there is no exact definition of the size of an ōdachi.