According to the 9th-century Greek poet Hesiod, the Chimera was a fire-breathing she-monster constructed from the head of a lion, the body of a goat, and the tail of a serpent. Hesiod told the tale of how the mighty Bellerophon, assisted by the winged Pegasus, "slew that fearful creature, great and swift of foot and strong / Whose breath was flame unquenchable."

The grotesque combination comprising the original Chimera inspired the application of that name to various other imaginary monsters, especially ones compounded from the parts of different animals, real or imaginary. By the late 16th century, such fantastic combinations had inspired the sense of chimera that names any wild or fanciful concept, especially a fabrication.

It took another few hundred years, until the 19th century, before chimera came to refer to "something considered to have a hybrid character." That's also the era when marine biologists borrowed the term to refer to certain members of the marine family chimaeridae, known more familiarly as rabbitfish and ratfish.

So when 20th-century botanists and geneticists needed a name for individuals, parts, or organs created from tissues of diverse genetic constitutions, it was natural for them to adopt the well-established chimera.