(Biology)the continued existence of organisms which are best adapted to their environment, with the extinction of others, as a concept in the Darwinian theory of evolution(生)（达尔文进化论中的）适者生存。 比较natural selection
柯林斯高阶英汉双解学习词典释义
N-UNCOUNT
生存
If you refer to the survival of something or someone, you mean that they manage to continue or exist in spite of difficult circumstances.
If you refer to the survival of a person or living thing, you mean that they live through a dangerous situation in which it was possible that they might die.
You can use the survival of the fittest to refer to a situation in which only the strongest people or things continue to live or be successful, while the others die or fail.