The Vietnamese currency unit (dong). Often written as 'đồng' or in katakana as 'ドン' in Japanese contexts.
ベトナムでは主にドンを使うので、現金はドンで持っておくと便利だ。
In Vietnam, the dong is mainly used, so it's convenient to have cash in dong.
このTシャツは200000ドンくらいだった。
This T-shirt was about 200,000 dong.
両替するときはドンの桁数に注意してください。
Be careful about the number of digits when exchanging to dong.