The word "Orisha means "Select Head" in a cultural context, Orisha is a reference to the various forces in nature that guide consciousness, according to Ifa everything in nature has some form of consciousness called "Ori". The Ori of all plants and humans is believed to be guided by a specific force in Nature (Orisha), which defines the quality of a particular form of consciousness. There are a large number of Orisha and each Orisha has it's own awo.
The Divine Messenger is generally known in Yoruba culture by the name Esu. Among those who practice Yoruba religion in the West, the Divine Mesenger is commonly known by the name Elegba. Esu is considered one of the many Spiritual Forces in Nature which is called "Orisha".