I asked for a definition of eugenics, not a list of the places you think it was attempted. Apparently, you cannot define the word 'definition' let alone know what the word 'eugenics' means.
Good day to you.
A list of examples is a form of definition.
But since you asked for a definition, I will give you my working definition of eugenics.
There are two kinds of eugenics, positive and negative.
Positive eugenics would involve an attempt to increase the number of offspring having some trait. You could do this by offering incentives, such as money, for having children. In agriculture, you simply plant more seeds from crops that have your desired characteristics. In animal breeding, you arrange mating between individuals having desirable charasterics.
Negative eugenics means preventing reproduction, either by force or by incentives. The extreme example is genocide, in which undesirables are killed. There are numerous examples of genocide in the Bible.