What is a fraction with a numerator that is greater than or equal to the denominator?

It is a top-heavy, or improper fraction but only if the denominator is positive.

It is not defined if the denominator is 0 and the numerator is any positive integer.

It need not be an improper fraction if the denominator is negative and the numerator is positive - and therefore greater - but of a smaller magnitude.

For example, consider 2/(-3): the numerator = 2 is bigger than denominator = -3, but the fraction is not improper.