There are several possible synonyms for "European Law Enforcement Organisation". One common one is "Europol", which stands for European Police Office and is a law enforcement agency that helps coordinate efforts to combat serious international crime and terrorism across the European Union. Other possible synonyms might include "European police force", "European law enforcement agency" or simply "European law enforcement". These terms all refer to organizations that work to enforce the law and maintain public safety within the European context, and could be used interchangeably depending on the specific context and context in which they are being used.