Ambiguity (in radionavigation)
The condition obtaining when one set of co-ordinates derived from a navigation system defines more than one point, direction, line of position or surface of position.
Reference: I.R.E. (modified)
Please note that this is the term as it stands in the original IALA Dictionary edition (1970-1989)
International Association of Marine Aids to Navigation and Lighthouse Authorities - AISM