descent

noun

• An instance of descending; act of coming down.

  "We climbed the mountain with difficulty, but the descent was easier."

• A way down.

  "We had difficulty in finding the correct descent."

• A sloping passage or incline.

  "The descent into the cavern was wet and slippery."

• Lineage or hereditary derivation.

  "Our guide was of Welsh descent."

• A drop to a lower status or condition; decline.

  "After that, the holiday went into a steep descent."

• A falling upon or invasion.
• A particular extension of the idea of gluing. See Descent (mathematics).