The Reason Why We Call the Oral
Multiplication Table "KUKU"
You know tha sometimes we call the English alphabet "the ABC's" or Japanese alphabet "AIUEO" or "I RO HA". That is to say, we use the very leading parts of them just as they are. The first mention of "Kuku" or a Japanese multiplication table in literature comes from "Oral Playing" written by Tamenori Minamoto in 970 for instruction to the royal children. This book begins with ９×９＝81, (pronounced in Japanese kuku hachiju-ichi). This is why we call it "Kuku".
multiplication table from "Oral Playing"