Description:
From the Greek meaning "she-goat" the Chimera is a fire-breathing creature that has the body of a goat, the head of a lion and the tail of a serpent. Some sources have represented the Chimera with three heads (the lion's head as the main, then the goat's head sprouted from its back, and the serpent's or Dragon’s head on its tail), but the popular myth tells of the single, fire-vomiting head. The very unlikely aspect of the chimera has gradually turned its name into a synonym of a vain dream.
Origin:
The chimera of Greek myth is the offspring of Echinda and Typhon. It has many other monstrous brothers and sisters.
Story:
The king of Caria, Amisodarus, raised the Chimera to terrorize the surrounding region. Chimaera main activity was to spit flames and devours all living.
The Chimera made great havoc in Lycia, so that the king, Iobates, sought for some hero to destroy it. At that time there arrived at his court a gallant young warrior, whose name was Bellerophon. He brought letters from Proetus, the son-in-law of Iobates, recommending Bellerophon in the warmest terms as an unconquerable hero, but added at the close a request to his father-in-law to put him to death. The reason was that Proetus was jealous of him, suspecting that his wife Antea looked with too much admiration on the young warrior.
Iobates, on perusing the letters, was puzzled what to do, not willing to violate the claims of hospitality, yet wishing to oblige his son-in-law. A lucky thought occurred to him, to send Bellerophon to combat with the Chimaera. Bellerophon accepted the proposal, but before proceeding to the combat consulted the soothsayer Polyidus, who advised him to procure if possible the horse Pegasus for the conflict. For this purpose he directed him to pass the night in the temple of Minerva. He did so, and as he slept Minerva came to him and gave him a golden bridle. When he awoke the bridle remained in his hand. Minerva also showed him Pegasus drinking at the well of Pirene, and at sight of the bridle the winged steed came willingly and suffered him to be taken. Bellerophon mounted him, rose with him into the air, soon found the Chimaera, and killed it with a lump of lead on a spear that he threw into the Chimera's stomach.
From Monstrous.com