descent
noun uk/dɪˈsent/ us/dɪˈsent/
(RELATION)
[ U ]血缘关系，家族关系;祖先;出身
the state or fact of being related to a particular person or group of people who lived in the past
She's a woman of mixed/French descent. 她是一个混血／法裔女人。
They trace their line of descent back to a French duke. 他们的先人可以追溯到一位法国公爵。
He claims direct descent from Mohammed. 他自称是穆罕默德的直系后代。
(ARRIVAL)
[ U ]不期而至，突然到达
an occasion when a group of people arrive somewhere, usually suddenly or unexpectedly
We weren't prepared for the descent of thousands of journalists on the town. 我们没想到数千名记者会突然来到镇上。
(POSITION)
[ C or U ]下降，下落;下沉
a movement down
The plane began (to make) its final descent into the airport. 飞机开始（做）最终下降，准备在机场着陆。
There is a steep descent (= way down, such as a path) to the village below. 有一条很陡的路通向下面的村庄。
(NEGATIVE CHANGE)
[ S or U ]堕落，蜕变
a change in someone's behaviour, or in a situation, from good to bad
His descent into crime was rapid. 他很快就堕落到犯罪的地步。