The abbreviation ZTM means:
Public Transport Authority (Warsaw) (in Polish: Zarząd Transportu Miejskiego w Warszawie), municipal transport authority in Warsaw, Poland Metropolitan Transport Authority (Metropolis GZM) (in Polish: Zarząd Transportu Metropolitalnego), municipal transport authority in the Metropolis GZM, Poland Zbrojovka Vsetín, a Czech weapon factory the IATA code for Shamattawa Airport, Manitoba, Canada