Descend, dismount, alight mean to get or come down from a height.
One descends when one climbs down a slope (as of a hill or mountain), a ladder, a step, a stair, a wall, or a tree.
- The plane began to descend.
- She descended the stairs slowly.
- Things are cooler and more damp as we descend to the cellar.
One dismounts when one gets down from a horse or from a bicycle or motorcycle.
- Emma dismounted and took her horse’s bridle.
- Cyclists please dismount at the gate.
One alights when one comes down from a perch or out of a vehicle (as a carriage, a car, or an airplane) with a spring or especially with lightness and grace.
- A thrush alighted on a branch of the pine tree.
- Two men alighted from the vehicle.
- Passengers for Lanzhou alight at Nanjing.