An obsolescent term for StandardAn authorised document, including specification, procedure, instruction, directive, rule or regulation, which may set mandatory requirements. Alpha-Numerical Route IndicatorAn Indicator associated with a Signal which indicates which Route is set. See also Position Light Junction Indicator, Miniature Alphanumeric Route Indicator, St.... See
also Theatre IndicatorAn obsolescent term for Standard Alpha-Numerical Route Indicator. See also Multi-Lamp Route Indicator..