The Collaborative International Dictionary
                    Mockbird
                    
                        
                
                                                                    Mockbird \Mock"bird`\, n. (Zo["o]l.) The European sedge warbler ( Acrocephalus phragmitis).
Wiktionary
                    mockbird
                    
                        
                
                                                                    n. A bird, the European sedge warbler (''Acrocephalus phragmitis'').