ad unguem
Latin phrase
                                                                                                                            
                                                            ad un·guem
                    
                                                                                                              
                                                                                                                                  äd-ˈu̇ŋ-ˌgwem  
                                                      
                                                          
            
                                
              
          
                                                      : to the fingernail : to a nicety : exactly (from the use of the fingernail to test the smoothness of marble)                                      
                
                    
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