inbreeding

名词 inbreeding:

1. the act of mating closely related individuals

1. The man, though poor, showed an inbred courtesy.
   那人虽穷，却表现出天生的谦虚有礼。

in.breed.ing

n.（名词）
The breeding of related individuals within an isolated or a closed group of organisms or people.
近亲繁殖：在一个分离的或封闭的生物群或人群内部进行的近亲繁殖
The continued breeding of closely related individuals so as to preserve desirable traits in a stock.
同种交配：近亲连续不断地繁殖，以此来保存某一血统的令人满意的特性