noun chi·me·ra \ kī-ˈmir-ə , kə- \
1) :a fire-breathing she-monster in Greek mythology having a lion’s head, a goat’s body, and a serpent’s tail
:an imaginary monster compounded of incongruous parts
2) :an illusion or fabrication of the mind; especially :an unrealizable dream
A fancy, a chimera in my brain, troubles me in my prayer — John Donne
John’s utopia was a chimera.
3) :an individual, organ, or part consisting of tissues of diverse genetic constitution. A hybrid created through fusion of a sperm and an egg from different species is a chimera.