Senses
九九 81 days of winter
The period of 81 days following the winter solstice, divided into nine nine-day segments
九九 multiplication table
The arithmetic multiplication table from one to nine
九九 Double Ninth Festival
The ninth day of the ninth lunar month.
九九 ninth nine-day period
The last of the nine nine-day periods after the winter solstice, marking the end of winter
九九 eighty-one
The product of nine times nine; 81