The bar or line that separates the numerator from the denominator in fractions is known as the solidus.
"The numerator and denominator are known as the fraction bar.”
That is a vinculum.
divider
The line between the numerator and the denominator of a fraction is the the solidus line
There is no special name for such fractions.
Vinculum is the name of the line between the numerator and the denominator.
There is no special name for such a numerator.
Informally, you can say the top of the fraction. But the only official name is "numerator".
It's sometimes known as the 'divison bar' or 'fraction bar'.
numerator
Numerator
That's the numerator.