What term defines the act of attacking or detaining a ship or aircraft and its crew or passengers on the high seas?

The term that defines the act of attacking or detaining a ship or aircraft and its crew or passengers on the high seas is piracy. Piracy involves unlawful acts committed on the ocean, such as robbery or hijacking, and is recognized as a criminal offense under international law. It specifically pertains to violent or threatening acts aimed at vessels in international waters, where jurisdiction can be complex and often requires international cooperation for enforcement. This definition captures the essence of what piracy entails, differentiating it from other concepts that might involve theft or deception but do not specifically relate to maritime activity. For example, ravaging typically refers to causing severe damage or destruction but lacks the specific context of maritime hijacking. Similarly, liberation implies freeing someone or something from captivity, which does not correlate with attacking or detaining vessels. Swindling denotes deception for personal gain, which again does not apply to the high seas context. Thus, piracy is the correct and most precise term for the act described in the question.