'Seed' in the Bible

And the king spake unto Ashpenaz the master of his eunuchs, that he should bring in certain of the children of Israel, even of the seed royal and of the nobles;

And whereas thou sawest the iron mixed with miry clay, they shall mingle themselves with the seed of men; but they shall not cleave one to another, even as iron doth not mingle with clay.

In the first year of Darius the son of Ahasuerus, of the seed of the Medes, who was made king over the realm of the Chaldeans,