Embargo Definition: This is an act of international military aggression where an order is made prohibiting ships or goods from leaving a certain port, city or territory and may be enforced by military threat of destroying any vehicle that attempts to break it or by trade penalties. This is an act of international military aggression where an order is made prohibiting ships or goods from leaving a certain port, city or territory and may be enforced by military threat of destroying any vehicle that attempts to break it or by trade penalties. The word has also come to refer to a legal prohibition of trade with a certain nation or a prohibition towards the use of goods or services produced by or within a certain state. Find you are constantly looking up definitions? Try our search provider (works in most modern browsers) If you find an error or omission in Duhaime's Legal Dictionary, or if you have legal term suggestion, we'd love to hear from you!