MLD

MLD may refer to:

Medicine

 * Manual lymphatic drainage
 * Metachromatic leukodystrophy, a rare neurometabolic genetic condition

Science and technology

 * Masking Level Difference, see Auditory masking
 * Mean log deviation in statistics and econometrics
 * Mixed layer depth in hydrography
 * Multicast Listener Discovery, in computer networking
 * Million liter per day, in environmental engineering

Other

 * ICAO airline designator of Air Moldova
 * Maldives, ITU country code
 * Maniac Latin Disciples, a street gang
 * Marine Luchtvaart Dienst, the Dutch Naval Aviation Service
 * Mutually locally derivable, a mathematical property of aperiodic tile sets
 * EU Money Laundering Directive
 * Miluo East railway station, China Railway pinyin code MLD
 * Monolingual learner's dictionary, type of dictionary designed to meet the reference needs of people learning a foreign language.
 * Moreland railway station, Melbourne