The formal name is
"All-purpose Humanoid Fighting Machine - Android Evangelion" (HANYOU HITOGATA KESSEN HEIKI - JINZOU NINGEN EVANGELION). 14 years of
time and an astronomical amount of
money were used to build the Evangelion in order to carry out the
Instrumentality Project. Able to both
deploy and
neutralize an
A. T. Field, it is the only fighting force that humans have to counter the
Angels. It operates on
electric power, and is limited to about 5 minutes of active time without external supply. Therefore it is normally supplied with electrical power through the
umbilical cable. (The
Evangelion Mass-Production Models from Eva-05 onward are equipped with the
S² Engine and thus do not need this
cable.) Originally the
Eva do not have
souls. For this reason, the soul of
Yui Ikari was made to dwell in
Eva-01.
The name Evangelion is thought to derive from "Eve", wife of Adam in the Old Testament, and "Evangel", the Greek word for "gospel".
Source: The End of Evangelion : Glossary contained within The End of Evangelion - Theatrical Program.
Follow up to Apatrix: Actually the most accurate (not literal, but accurate) translation of Neon Genesis Evangelion is Gospel of the New Century