Japan domestic marketᵂ (JDM) is a vehicle manufactured for Japan's domestic market i.e. to be sold in Japan. Thus it differs for worldwide market vehicles in small ways. For example JDM 1200s had all-red tail lights, while Europe/Australia got amber turn signals.
JDM models can be manufactured anywhere, say at Honda's Ohio plant. JDM only mean it meets the Japan home market specifications and is intended for sale in Japan.
JDM does not mean Japanese car. A Nissan manufactured in Japan to US specs and immediately shipped off to America is not a JDM model.
The term JDM can also be applied to specific parts (those designed to Japan-market specs).
related: USDM: United States domestic model ADM: Australia domestic model
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