资料来源 : pyDict

嗯!

资料来源 : WordNet®

Er
     n 1: a trivalent metallic element of the rare earth group; occurs
          with yttrium [syn: {erbium}, {atomic number 68}]
     2: a room in a hospital or clinic staffed and equipped to
        provide emergency care to persons requiring immediate
        medical treatment [syn: {emergency room}]

资料来源 : Free On-Line Dictionary of Computing

ER
     
        {Entity-Relationship}

er
     
         The {country code} for Eritrea.
     
        (1999-01-27)