Tuidi is the Okinawan pronunciation. In spite of Okinawa becoming a property of Japan starting with the Meiji restoration circa 1868, certain terms, in karate particulary, persist, as does the Okinawan language as a whole, especially among older Okinawans.
Tuidi techniques are first taught against grabs - the wrist, the shoulder or lapel, then against chokes and such. Once a basic movement is learned, then techniques are sequenced together in flow drills or defensive sequences.
By starting with wrist attacks, the defenses can be more easily learned in their isolated form before applying them to more active attack scenarios.