semen

The word 'semen' is a direct borrowing from Latin, where it meant "seed" or "that which is sown." This Latin term itself derives from the Proto-Indo-European root séh₁mn̥, also meaning "seed." The conceptual link is profoundly agricultural: just as a seed is planted in soil to generate new plant life, the male reproductive fluid was seen as the "seed" planted in the female to generate new human or animal life. This ancient metaphor perfectly encapsulates the biological function, with the Latin term passing unchanged in form into scientific and general English to denote the male generative fluid.

The word is a simplex loanword from Latin. It cannot be meaningfully segmented into smaller, independent morphemes using its modern English spelling.