jockey position
Rear entry sex position wherein the receiving partner is lying prone on front, while the penetrating partner does so while kneeling or crouching on top with legs spread on both sides of the receiving partner, as if they were riding a mount.
Not to be confused with doggystyle, leapfrog_position or generic from behind positions, in which the bottom is on all fours or in ass up position. If the receiving partner is lying on back instead, then missionary position would be appropriate. Whereas if the top is straddling the bottom while also lying down, it's the speed bump position instead of Jockey.
If penetrating character is flipped, it becomes reverse_anvil_position.
Similar position where penetrated character is flipped: (to be found).
See also
This tag implicates prone_bone_position (learn more).