A decimal for ⅓ is called a repeating decimal because when dividing 1 by 3, the result is a non-terminating decimal that repeats a certain pattern of digits. In the case of ⅓, after the decimal point, the digit 3 repeats indefinitely. This is represented by the symbol "..." after the digit 3. Thus, the decimal equivalent of ⅓ is 0.333..., where the digit 3 repeats forever. Hence, it is called a repeating decimal.
