Minimum descent altitude or minimum descent height
urn:aero:airm:1.0.0:ContextualModel:ATMBusinessTerms:Minimum_descent_altitude_or_minimum_descent_height_
A specified altitude or height in a non-precision approach or circling approach below which descent must not be made without the required visual reference.
Source:
ICAO
Synonyms:
MDA/H; minimum descent altitude/height
Abbreviations:
MDA;MDH