Answer:
Magnetic quantum number.
Explanation:
Orbitals with the same principal quantum number and the same l value belong to the same subshell.
The magnetic quantum number, ml distinguishes the orbitals available within a subshell, and is used to calculate the azimuthal component of the orientation of space.
The value of ml can range from -ℓ to +ℓ. The s, p, d, and f subshells contain 1, 3, 5, and 7 orbitals each, with values of m within the ranges 0, ±1, ±2, ±3 respectively while containing 2 different spin electrons.