Hebrew: mashiach; yeshnu ha-nuvtsedi
Arabic: 'as-sayyid 'al-masīh
The word comes from the Greek translation of Messiah, "the anointed one". In Greek, the word "Chrism" originally means perfumed oil.
There are a few contenting explanations to the origins of the word, both representing deviations from an understanding of Christian history that most Christians will find acceptable. One links the term to Ancient Egyptian religion, the term "karast", used for the embalming in oil. This theory links "Christ" to the myths of Horus, and his triad with his parents, Isis and Osiris.
Another explanation links to the Hindu god, Krishna. There are in fact numerous mythological similarities between Jesus and Krishna, but the geographical distance from India to Judah represents a major challenge to the probability of this theory.
In Christian theology, the terms "Christ", "Messiah" and the name "Jesus" are effectively overlapping terms. The terms "Christ" and "Messiah" cannot in many cases be distinguished, except from one: while Messiah can be used in both Judaism and Christianity, Christ is used only with Christianity. When a distinction is made between "Jesus" and "Christ", the first may be preferred for earthly events, while "Christ" is used in questions relating to divine qualities The confusion, or flexibility, between these terms was even larger in early Christianity. It is really first in modern theology that there have been attempts to make sharp distinctions.
It was from the term "Christ", that the designation "Christian" was derived, indicating the followers of the teachings attributed to Jesus. The first known occurrence of this is from around 50 CE, recorded in The Acts, telling that in Antioch Jesus-followers first came to call themselves Christians.
The understanding and definition of the nature relating to the Christ was of such central importance that it became the main issue of the first 4 ecumenical councils, from 325 until 451. The theological problem was that it appeared wrong to define Jesus as identical with God, yet to define him as secondary to the heavenly God. Another challenge was the question of Christian monotheism; was Christ another deity?
Issues debated were Christ's relation to God as well as the understanding of his divine and human natures. The background for the disputes, were the many theories in circulation on the matter in the early churches. The teachings of Arius (see Arianism), stating that Christ was less than God, but more than man; Christ was divine, but he could not be called God. Adoptionism claimed that Jesus was simply a normal man, adopted by divinity upon his baptism or after his resurrection. In some Gnostic orientations, Jesus only had an apparent body; some Gnostic orientations stated that anyone could become Christ.
At the Council of Nicaea in 325, Christ was called "begotten, not made", and "of the same essence as the Father".
In Jewish religious history, the term equivalent to "Christ" meaning the "anointed one", could be used for priests, prophets as well as kings. In all cases it indicated a close relation to God, superior and even supernatural qualities.
The field in theology dealing with the life, teachings, works and identity of Jesus, is called Christology.
In Islam, where Jesus is revered as a prophet of God, he is referred to as Messiah. Although denying Jesus being a divine creature, Islam define both his conception and birth as miracles, and that he never died (even less, was crucified) but was raised to Heaven by God.