ablution
- n the ritual washing of a priest's hands or of sacred vessels
abm
- n a defensive missile designed to shoot down incoming intercontinental ballistic missiles
abnegation
- n the denial and rejection of a doctrine or belief
abnegation of the Holy Trinity - n renunciation of your own interests in favor of the interests of others
abney level
- n a surveying instrument consisting of a spirit level and a sighting tube; used to measure the angle of inclination of a line from the observer to the target